Blown rectifier tube. DaleH, May 4, 2009 #6.

Blown rectifier tube This should deflect the meter at first, but then get to a higher and higher resistance as the filter capacitors charge up from the meter. At first, after I fix the power cord, I got 350vdc to the VVR in and it dropped 25v out to 325vdc. Moderator. Continuing use of the site implies consent. Besides that, tube rectifiers kill the headroom of an amplifier. Your choice may vary . One thing I've noticed: The Mullard rectifier tube seems to glow very brightly when plugged in, and it even makes a slight humming sound. A. . Like Usually when the rectifier tube goes bad it will blow a fuse or exhibit low voltage output depending on how it fails. If the filament is intact you get a “good” reading and if Tube manufacturers usually doesn't recommend using damper diodes as (50/60 Hz) power supply rectifiers,probably because they were designed for short pulse type operation at TV horizontal line frequency (15. While you're putting on suspenders with that belt, solder in two solid state diodes. Tried to turn it on and nothing today (as I do every evening), and nothing Being a tube newbie, haven't had this experience before, thought they should last a lot longer than this (build date of the amp is Jan t This and the blown tube were most likely the culprits in the humming. It's important to note that Mesa amps are designed in such a way that even the most inexperienced and tube-terrified musician can change a bad tube as easily as you would change a light bulb. A few months ago at a gig the fuse blew and I replaced a rectifier tube and put a new fuse in and all was good so that appeared to be the issue. J. SSE Blown fuse, arcing in rectifier tube. Post n°1; Rectifier Tube sparking - blown fuse. Got them installed, turned on the amp, pushed the standby switch to on position and now all of Another simple mod you can try is to use a solid state, FW rectifier plug in there instead of the tube rectifier and install a 10 watt, 100 ohm resistor from the rectifier tube socket lug 8, to the first filter cap. The solid state diodes keep the AC from getting to the filter caps if this happens. kagliostro. With my one good rectifier tube, the amp played perfectly nicely. Rectifier Tube sparking - blown fuse. Rectifiers come in two formats: tube and solid state. This reduces the inrush current of the transformer which protects the fuse from being blown by switch on, and also dampens the heater inrush current a little bit. Once you get to over 50K or so, you can be sure that the filter caps are not dead shorted. 1N4007s work fine in that amp. They report that the fuse blows or pops, and they may receive a defective tube. It looks to me like in standby the amp is running through the 6 volt circuit to heat the tubes, the 5 v circuit to heat the rectifier tube filament, and the high volt circuit that runs power from the transformer through the rectifier tube and the standby switch just connects the power from the rectifier tube into the rest of the amps circuit. If your amp has a tube rectifier proceed to step 5. this guitar amplifier is very sensitive to vibration and someti It sounds better than my China EL 34(Audcom) and i really like how the Audcom sounds with JJ KT77's in it. Rectifier diodes are simple devices that are easily dimensioned to withstand the maximum operating load permanently. As those tubes use a different secret sauce on their cathodes. Any one seen this before? Different tube-rectified amps have different voltage requirements, and thus use different values of tube rectifiers. Howe can I check if the rectifier tube is gone. 5. Could also be the rectifier tube. [ Follow Ups] Thread: [ Display however (the page that shows the outer chassis layout from the top), the circles that represent the rectifiers have 6CA4 printed under them, but have "6V4" hand-written within each circle. High voltage AC is Before you have a tech look at it have all the output tubes tested. I plugged it into a small homebrew power suppy laid out in the usual fashion: Stancor PN 8403 250-0-250 tranny; rectifier tube, 40 uF, big, but unknown inductance, junkbox choke, 40 uf, 110K bleeder, and measured the voltage output: Fried Valve Art 5AR4: 383 volts DC, 135 mV AC; RCA 5Y3: 371 volts DC, 45 mV AC. Check all your wiring and voltages (amp instructions) and use a SS rectifier as advised by tubes4hifi. FGub likes this post. Pull the rectifier, which disconnects the high voltage secondary. 9. More tubes glowing is a good thing. No rectifier arcing or blown fuse, but the quad cap smoked. Post reply Similar threads. If the head powers on at all, the rectifier tube isn't the culprit. These amps are hard on rectifiers - I had good luck with the WZ68 SS. In a power tube it would have no effect. 2016-04-02 10:17 pm #14 further thought I now wire a UF4007 in series with each GZ34/5AR4 plate as this greatly increases the PIV rating of the rectifier tube and is effective in preventing warm up arcing in most cases One of the 4 sections starts to work its way towards a dead short and when the rectifier tube trys to push 440 volts DC into a near dead short the rectifier puts out the fireworks that you describe and then usually the fuse blows and/or the rectifier tube bites the dust. I'd normally be inside confirming the power supply is ok, then the rest of the stages have When the rectifier first starts to conduct, it is trying to charge a very low impedance load, namely the capacitor. If the fuse did not blow 5. These tubes are shipped in a high quality dual box or single box for rectifiers. Ordered replacement rectifier tube. If not, re-install the original tube and move your spare to the next The classic indication of a broken amp is a dark pilot light. Installing a resistor at this location will control the peak currents drawn and improve regulation, providing nearly the same B+ level that a GZ34 would under any Blown screen resistors and more. - Rectifier tube was defect after 4 months, changed for another. The new FREDs arrive tomorrow but at this point it would seem that I need a new rectifier tube. As I mentioned Rectifier tube blows. May 13, 2009 I really hope your second rectifier tube was not shorted also, but if you know for sure, then its the filter cap associated with the 2) Protection in some cases of the power transformer getting blown on a tube short should the mains fuse be late 3) Prevent inrush arching in some rectifier tubes 4) Protection downstream should the rectifier tube get a plate to cathode short, the circuit would still be getting DC instead of raw AC because the diodes are there. Turned on the preamp and volume was very low and distorted. Tube is blown there are whitish marks on the tube and after that I accidentally dropped it. A 5U4 can work, but the robustness of the rectifier tube comes down to the way it was assembled. If you have a spare tube of the same type it’s good to substitute it in place of one in your amp and then listen for the noise. Even though we can engineer a similar amount of voltage sag into the power transformer, purists may see the Some tube amps are really good to use as tube testers when you understand what tube sockets correlate to which channel. PHONE & Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Tubes4hifi VTA tube amp and preamp kits and all Dynakitparts. If it blows, a rectifier tube is bad. But Now, one channel is 'out' » M-125 problem resolved, rectifier fried » Rectifier and blown fuse Now, if there's a tube rectifier, that would need to be installed and confirmed to be operating ok before starting with the first stage tube installation. Put the rectifier back in. 550v. Now, the rectifier tube only has 260vdc out. IOW, you may have a 40V drop across a 5Y3 if the load current is 100mA, but Some nasty sounds inside amp and blown Slow Blow use. Joined: Sat Nov 25, 2006 9:05 pm Posts: 665 Location: north york, ON, CA Recently,one of my mono block tube amps shut off,no more power to it. Level 5; Posts: 7624; Re: Rectifier Tube Chart/Cross Reference Just remember, the voltage drop across a rectifier tube is not a constant value. kta-hifi. Single Ended Triodes (SETs), the ultimate tube lovers dream. (3A slo-blo) 2. I fixed the wiring, powered up the amp, and it worked but after about 2 hours of running the amp died and I found a blown fuse. If the voltage of the power supply fluctuates the output will be affected. Main fuse The Internals of the JJ GZ34S Rectifier Tube. I came across the schematic and checked all tubes individually. If the fuse blows, you've probably got a stuffed rectifier. Leave the filament wiring connected. ) a design flaw or they know something about the tube. Paid Member. Please suggest better translations. The only other situation that I can think of where I've experienced rectifier tube arc-ing in the past is when I've added too much filtering (too high UFs) to the 1st I received an european amp with a GZ32 rectifier tube. I owned one of these amps and most likely either a fuse or that. If the 6CA4 runs on its own isolated winding, it could be shorted with no ill effects at all. Monday-Friday: 8:30am-5:30pm Pacific Saturday: 9am-5pm Pacific Please call ahead to schedule demos! info@upscaleaudio. Blown Fuse . DaleH, May 4, 2009 #6. The effect will be somewhat similar to compression, but can also have other negative byproducts. Most modern GZ34/5AR4 tubes, although rated at 250ma@full Blown rectifier tube and fuse. They should To provide a better shopping experience, our website uses cookies. 80022 www. Amp powers up . jpg. Power: Lose clarity, power, lack of "punch" when My guess about the GZ32/5V4G rectifier tube was correct: I learned that at the $. I found out that it was the rectifier tube that was blown and I swapped it out for a local 5AR4 tube that I found at my neighborhood Guitar Center. 2023-07-19 1:58 am #14 I had a backup pair of Mesa STR440's that I put in until I have time to mess around testing the broken tube. Member. Tube wise currently using an RCA 5U4G rectifier tube using a pair of RCA 12BH7 Dimple Getter along with a Hytron 12BH7. 3. There is no slow warm up. Reply. But more often a rectifier will short/arc and blow a fuse when it goes bad. Forums. Just to think of all the mercury in old thermostats and fluorescent lamps which are broken in the households. Must modify the heater powersupply. Replaced 5 amp fuse with spare 7. I have successfully designed and built amps that have replicated that soggy bottom, Hey All, Several days ago, my 05 began to blow all the fuses (HiFi Tuning tweak ones too. Replaced rectifier tube with a Valve Art 274b (loose base) 8. ) Power tubes wear out more quickly than preamp tubes, but progressively so you don't usually notice the drop in performance until you put a new set in. If you like having the old school rectifier tubes, these also can be replaced one at a time. Problem - Fuse blows about 10 to 30 seconds after turn on and/or sparking inside rectifier tube Areas to check - bad rectifier tube, bad DC high voltage power storage (usually a bad quad cap), bad (shorted inside) output tube @PeterCapo : I did find a broken connection in the socket, and have repaired. Post Cancel. A 5Y3 will NOT live long in a typical SSE. He’s been trying to restore the radio to proper working condition. 931. A faulty rectifier tube. I placed the rectifier tube and two output tubes into the left side, and the rectifier tube arced and the 3A fuse blew. Power tubes are kt120, Drivers are 5963 hp branded RCA. The heaters from these are connected in series, and I'm fairly sure the rectifier is blown, as there is no conductance across the two heater pins ( as opposed to climbing resistance on the two other tubes). 3 A instead of a 3 A (one or both). Greetings all - I wrote Bob about this issue directly (email copied below) but wanted to reach out to the community to see if there are any folks awake with any A tube rectifier may make the cut when the goal is to produce a vintage-correct reproduction amp. Power down, replace the fuse, put in your spare rectifier My VTA ST 120 blows the rectifier tube. Jump to Latest T. All's good, but a bit of tube "spitting" sound from R channel. I’m curious - wouldn’t there be no output with a blown As a mater of practice, any time a fuse blows it is wise to remove the rectifier tube, replace the fuse, and start up the amplifier again WITHOUT the rectifier tube plugged in. Bruce Mission Amps Denver, CO. Solid State Rectifier: If your amplifier has a solid state rectifier then the rectifier tube replacement so that you do not accidently touch the exposed lethal voltages on the connections. I examined the power amp and power supply, put in a new fuse and new pair of 6V6 power tubes and started testing. I installed another fuse and tube and Home. Pull out the rectifier and replace the fuse. Exact same result as (2) 4. I also noticed that the last tube with the intact screen resistor lights up more brightly (which I think is the heater filaments) when I put the switch on standby. Attachments. If you want that spongy, vintage sound, there are other ways to do it. Power up. Its job is to turn AC current from your wall socket into DC voltage. If the bulb glows brightly without the rectifier then you may have a shorted PT. The 5U4's are in parallel, so the amp will 'function' with one tube. Some are switching out soon getting my very first tube amplifier, so basically i wanted to make a thread advising people what not to do to avoid blowing your tubes/how to tell if they are blown/ and how it can be fixed Diagnosing Power & Rectifier Tube Failures: Most of the calls we receive about an amplifier blowing fuses turn out to be tube related. The only one that wasn't in a good state was a the rectifier, a GZ32, which had their 🔔 Get your tools here: Multimeter: https://amzn. 2011-02-13 9:58 am #1 Just becuase a rectifier tube "lights up" does not mean that it is still good. Leo_Gnardo Posts: 2585 Joined: Thu Sep 27, 2012 1:33 pm Location: Dogpatch-on-Hudson. They do work fine in 6V6GT builds that incorporate a lower voltage power transformer for about 320 volts of B+. Most gear these days that use tubes are solid state rectified and pretty well eliminate that issue. sKiZo. 450v per The rectifier tube in either the VTA ST-70 or VTA ST-120 (or a stock ST-70) is THE tube most likely to fail. I'm told these are typically long-lived tubes so I likely had a weak one from day one. Now a shorted rectifier tube will not kill your power transformer and your filter caps. And all this from a brand new,unusednon broken in pair. To be honest, I choose my rectifier tubes for guitar amps based on how much they physically rattle. Heater glow tends to imply that In most cases a blown fuse is signaling a shorted or otherwise failed power or rectifier tube. It's a Weber kit so I'll assume you are using a copper cap rectifier in a tube socket [1]. com 909. I'm waiting now for new rectifier tubes from an eBay purchase, and all should soon be well. Posted: Thu Jul 21, 2011 8:05 am . How do you know the rectifier tubes are blowing and not just the fuse? Are you using slow blow fuses? I would not be surprised to find a bad filter capacitor in the power The rectifier tube provides the high B+ DC voltage and when the tube goes bad you get no sound. com products Nopted that rectifier did not seem warm at all. I strongly recommend people replace these factory supplied (either bare bones basic Chinese made Shuguang or new production Russian Sovtek tubes in the newer models), with quality NOS rectifiers. Turned on amp in same order. Fuses have always blown before anything catastrophic. Replaced fuse, blew again. @bdbell, Both of my ARC vm220 with kt120 tubes did the same resistor thing, R81 (1) 1 ohm and R80 (1) 100 ohm. Discussion in 'Audio Hardware' started by shnaggletooth, May 4, 2009. Turned on R channelstock 5u4 rectifier tube flashed, fuse blows 6. In the case of amps that have Rectifier tubes, the culprit can be either a bad Rectifier tube or a bad Determining if a Blown Fuse is the result of a Bad Tube: Make sure the POWER and STANDBY switches are in the off position. Comment. Now power up. However, In some amplifiers, the rectifier tube is on a separate winding. Remember, I'm assuming our OP doesn't have any test gear or isn't comfortable around high voltage. If the tube isn't lighting, and doesn't heat up either it may be the Rectifier The two main symptoms of a power tube problem are a blown fuse or a tube that begins to glow cherry red. If power section really is fine, could you have a bad preamp tube? Like broken bad? Top. See what you think at ~. The 5 diode 4 watt amp runs the tube heaters on unfiltered DC, and uses filtered DC for 170 volts of B+. net. Called ARC service, spoke with service manager, they had the resistors in stock, ordered several to have on hand, removed and replaced broken items, replaced suspect tube(s), re-biased and they've been working fine. I ordered a new JJ GZ34 / 5AR4 Vacuum Tube rectifier and some fuses 3a at 320 volts. Pulled the bottom off and the fuse was smoked but no evidence of other If you are having power tube issues, blowing fuses, and or power supply problems (killing the rectifier tube) definitely have the amp looked at by qualified Mesa Tech. The 8 diode amp makes 15 watts of output power, has a bridge for 170 volts for the screen grids and tube heaters, and a full wave doubler for main 340 volt B+. Blown rectifier tube and fuse. 550v per tube is going to be very hard on the rectifier. no fuse blowing but only 260vdc going in to VVR, coming out it's 35v. Understanding vacuum tube test scores can be the difference between adding an amazing valve to your collection and wasting $100. Amp is running off a variac kept at 115v. Removed the cover and saw that the rectifier tube was dead. Or your rectifier. Joined 2004. Last one was 5ar4 tung sol. If it’s gone you know you removed the bad tube. Amps with valve rectifiers often blow fuses because the rectifier valve is going short circuit. . SS mode & rectifier mode. Look what I found! - Any one tried these tubes in The Mark V 90W Except in 40+ years of toobing, I don't think I've ever blown up a 5Y3! Logged 1 Like mresistor likes this. New posts New media New media The rectifier tube is a J&J which I have read is unreliable sometimes, but odd two have blown in a row. Last edited by Raja_Kentut on Thu Jan 04, Tube rectifiers have no switching noise hash the gets into the audio stream, while SS diodes unless they are of the fast recovery type do 1. [Tube rectifiers are great for MI, not so much for HiFi - from an electronics Fender Hot Rod Deluxe Blown rectifier diode(CR4 . Anyone use them? C'moon guys . Dom . The mod's purpose is to stop the capacitors from discharging through the power transformer secondary in the event of a tube rectifier failure. The SSE runs the rectifier tube pretty hard. Plus its a tube amp. Last edited: 2023-07-19 1:58 am. So after inspecting the other rectifier tube to make sure I put it in correctly, I turned it on. But now this new fuse has blown under the same circumstances, amp on about 1/2 hour. Some have reported blown rectifier tubes in past but not lately after switching from a 5z4p for stock rectifier. Both are really easy fixes. Tubes check out good to excellent and amp still worked through gig although ugly distortion no clean sound. Bob. Try biasing lower, running at . Power tubes need to be It's a Dynakit, lightly restored by the tube amp tech who sold it to me. No glow, and the getter flashing is severally discolored. You can use an old blown rectifier socket. But I think the Mullard 5AR4 is the best out there and If it turns out to be a blown rectifier tube you may want to consider a rectifier with greater current capacity. jeffs01879 Active Member. Here's the story: 1. Sometimes you will see a voltage drop with a weak tube, but you need to be able to measure that. tovaskai. 2058 Wright Avenue La Verne, California 91750. I didn´t have spare fuses, so I borrowed a JCM800 head and got through the gig, and when inspecting my Mark V yesterday, I found that the rectifier tube was indeed the culprit. For future reference, if the fuse blows, replace it and power the head on (leave in standby). I'm sure the Mesas are colder than the JJ HiGains they replaced, but for now it's working fine. The current draw is a milliamp parameter off the cathode of the tube an is what is measured when people (But you do need a spare fuse, since a blown rectifier tube will almost always take it out - and in a 3-ch Rectifier, you must physically remove the blown tube as well. FGub. power tube's screen resistor intact. 2018-12-29 2:37 am #1 2018-12-29 2:37 am #1 My SSE has been running beautifully for the last 5 years and almost untouched, the The rectifier tube is black on the glass above the base, so I would assume that it needs replacement. On an ST120 you are using about 50ma per output tube, plus about 17ma for the driver board, so 217ma total. " The way you just wired the diodes, you could pull the rectifier tube it is completely out of circuit now. ; Inspect the tube sockets - make sure there are NO burn marks (any burn marks must be removed before the amp will work). I can't help still having my fingers crossed, but that's just me. Replaced fuse, watched filaments start to come on, then arcing in rectifier tube and blown fuse. John Rectifier tube. A blown fuse often indicates a tube gone bad. It was working with the GZ32 (I recaped the amp before). Turns out it was a bad tube. The amp is using a pair of Amprex 7308. You have a bad power tube. Sometimes with a dual element rectifier just one half will go south without shorting and this will be the low voltage condition. 1 of 2 Go to page. Tube preamp failures can cause impulses in power amps which can damage speakers. Like Dislike. by Roy Mottram Mon Apr 23, 2012 7:01 pm. Rectifier has tested ok with no scorch marks. Fuse blows (or power Using the original GZ34s rectifiers as supplied in the kit. Tube printing with real gold The Rectifier tube is used as a diode, so it either works or doesn’t work, they don’t (noticeably) slowly wear out like a power tube. Usually takes the fuse too. At Not the problem. Although tube rectifiers are fussed over the most, all tube-based guitar amps have a rectifier of one sort or another. Post subject: Power spike -Blown rectifier tube. We hope you enjoy our selected products and with each purchase you will be bringing us closer to British valve manufacturing again. kevinkr. Turned out that the rectifier had blown, changed it an now works, Don't know why rectifier burned out, but 5. 41 cost of one more blown fuse. Both replaced. After a diagnosis it was determined that a power spike was the likely cause. No red plates, but a flash inside the tube, at its base near the pins connectors. Turned off the amp as I'm not comfortable with 274b tube having loose base. - Changed 6DJ8 tubes for JJ E88CC goldpin. I I checked the solderings on the rectifier tubes and checked for a blown fuse (not neceessary couse the other tubes all lit up. Pull the tubes and unsolder the center tap. - Changed ECC82 for 6N6P. Nothing unusual noticed as the fuse blew. Elekit TU-8500 Stereo Tube Preamplifier Kit; Elekit TU-8550 Stereo Tube Preamplifier Kit; Elekit TU-8600S 300B Tube Amplifier Kit - Lundahl Version; Elekit TU-8850SE Stereo Tube Amplifier Kit; Elekit TU-8900 300B/2A3 Tube Amplifier Kit; Elekit TU-H82 Hybrid Tube Amp Kit; Model 16LM Mono Integrated Tube Amplifier; Model 8LM Mono Integrated Tube In this video, I will show you how to diagnose a vintage guitar amplifier Fender Twin Reverb. Speakers are khorns A few mA of leakage in a preamp tube might cause hum. 4. A spongy tube rectifier can lead to power supply voltage fluctuations dependent on signal and load. Still 5. Rectifier tube failures rarely have similar consequences yet could on some occasions but not as often. Part numbers for rectifiers in your amp are, for example, 5AR4, GZ34, 5U4, EZ81. Thread starter inlet; Start date 2018-12-29 2:37 am; Status Not open for further replies. Also, the DC rectifier for the filament supply and a few of the resistors for the channel switching power supply, which is fed from the filament taps of the Power Transformer, were Hi I recently received a radio from the 30s which wasnt working at all. The driver and output tubes filaments glowed as normal for the brief period that it was plugged in. Each tube is scrupulously tested and only the best get badged with the Brimar thermionics logo. The last two modifications are to change sound and this is very personal. On power up a bad qualitu fuse or underrated one will blow even with the secondary disconnected For example a . His most recent pain has been with the rectifier tube. If the fuse now blows, you have an overload somewhere on the load side of the rectifier, You might find the power tube's idle current drop a bit. I've had good luck with new production Mullard GZ34 in my guitar amps, though I don't have any hifi gear running that particular tube. Main power fuse gets blown. Post n°19; Re: M-125 new(er) build - copper cap rectifier. Blown fuse. From what I read it could be a loose tube, so I realized that the far left tube (which I now know is the rectifier tube) was a little loose so per google I took it out and made sure it was back in snuggly, I flipped it on and let it warm up and when I took it So keep the rectifier tube. Just the amp going dark. If the remaining tubes in the amplifier light up, then the amplifier is fine. But the GZ34 blew quickly after the heating period, as the main fuse. It’s actually original to the preamp (as are all the other tubes). Thread starter tovaskai; Start date 2011-02-13 9:58 am; Status This old topic is closed. You may have a shorted tube. Top. The power outage did not blow any fuses in the house or damage any other equipment. That was a 5Z3P --> 274B swap. Re: Blowing fuses. I currently left the rectifier tube in as well as the pre amp tubes and no excessive The rectifier tube upgrade made the most significant improvement. Sep 14 The rectifier tube was blown, so I pulled that one out; I was looking at the other tubes and the preamp tubes are all unlabeled made in China 12AX7s figure I'll probably swap those out at some point. So, with a resistor after the cathode of the 6X4 and a lower value capacitor, the tube is allowed to charge the capacitor more slowly and One power supply uses HEXFREDs, a little expensive, but no more expensive than a very good tube rectifier, and no 5V winding needed. If the rectifier had failed the fuse would most likely have blown and the pilot wouldn't come on at all. I have been leaving the DRRI "on" in my studio a lot, for No vacuum tube rectifier lasts forever, that's why you see so many rectifier tubes in those boxes of tubes on ebay taken from "dad's repair shop". It's like two half-wave rectifiers in series; the SS diodes "do the heavy lifting", while the 5AR4 looks pretty and supposedly smoothes-out the hash from the 4007s. When I remove them the issue goes away even away. IMHO, a single GZ37 barely meets the current demand of the ST120. First, without the rectifier and Plugged in amp with rectifier tube only, 290vac on each sec. I did a search here for blown fuses and found the usual comments, "reflow solder joints, ect". Case closed. ElArte. missionamps. Rectifier's are probably the first thing to go. One of the EL34 output tubes had blown,or shorted,taking out the fuse. Thread starter dazzo; Start date May 13, 2009; dazzo Member. Turn it off and install a new rectifier tube and enjoy some music. The tubes in your amps require high DC voltage Looks like the 5AR4 rectifier tube in my Supratek sauvignon has gone this evening. No bright tube displays. Next Last. There would also be no Tube Guitar Amp Troubleshooting. Can't see any way to use those circuit board Tube Notes: Each MC30 is loaded with a carefully hand selected set of vintage driver and rectifier tubes, along with current production Tung-Sol 6L6GC output tubes. To see if this is the case, locate the To do a good job of mimicking the voltage drop of a GZ34 tube, there should be a 50 ohm 10 watt resistor installed BETWEEN the output of the SS rectifiers, and the FIRST filter cap. The writing on the If your amp has a solid state rectifier proceed to step 4. Heavier-duty tube rectifiers include the GZ34 (5AR4) and the 5U4G; these tend It arrived with one dead 6V6 power tube and a blown fuse. If there's nothing obviously wrong, remove the power valves and rectifier valve, replace the fuse. VVR isn't working. I’m I have an old record player here that uses a UY85 as a rectifier, along with 2 UCL85s as the amplifiers. Some failures can be an intermittent short and some can Usually when the rectifier tube goes bad it will blow a fuse or exhibit low voltage output depending on how it fails. My guess is that this is a bad power tube. Had a gig last night and one of the recto tubes blew the fuse again, replaced the recto tube with a spare and new fuse and it blew again about 30 mins later. The rectifier tube is the tube most likely to go bad on these amps. com When I plugged everything back in, the rectifier after about a few seconds gave a heck of a lightshow and R1 started glowing. The broken tube is a 6CA4, a full-wave rectifier, whose spec sheet I've attached. If the fuse blew, there is a problem with the rectifier or the wiring to them. The FREDs on the SSE board are an alternative rectifier (ie you can have a tube rectifier -OR- a Solid State rectifier, but not both). com/ElectroUni So last night my amp was making a scratchy sound when I would push it, so I naturally went to google to see what the problem could be. If there’s a bad fuse or rectifier tube that’s blown, you’ll need to change both of them. Go. Possibly some caps have been taken out too. Post n°3; Re As to your problematic CD player, if it's not the fuse, it is possibly a blown rectifier tube (5AR4). Corona. Bias before failure was steady at around the . 2. If you replace a blown rectifier diode, it's very likely you'll keep blowing fuses and possibly diodes until you find the actual culprit. Guitar Center had the tube in stock if I remember correctly. I left the amp on all afternoon, and sat back down for more listing this evening. In today's 5Ц4С rectifier, double-anode tube (This data is based on google translate and cleaning up the text to some degree. Try it again. photoenergy Posts: 4 Join date: 2014-01-06. This may result in increased hum because of the filament voltage Rectifier: Usually work great until failure, then causes fuses to pop when bad. Design note: The recommended design for 5U4 and 5Y3 tubes is to take power off pin 8 of the filament. Remove all the POWER and RECTIFIER tubes ** (See Note 2 below). 4 customers mention "Blown fuse" 0 positive 4 negative. Sponsored content. 112. 9686 DEMOS BY APPOINTMENT. Blown filter cap. New posts Search forums. 75 KHz) ,though I never had any reliability or reduced lifetime issues with damper diodes used as power rectifiers. to/48S1Ry8 Bridge Rectifier: https://amzn. Remove the KT66s for the time being. It could have blown the fuse then but I noticed it yesterday. With that said, if the 5U4G has been delivering the goods don’t fix what ain’t broken. I keep bias at 450ma via an internal auto bias board. damn it!) and wouldn't power up. 52 Bill. This happened in a tube amp of mine a couple years ago. If it doesn't, power down. Reconnect the rectifiers to the first filter cap and disconnect the first filter cap from the output transformer and inductor or screen grid dropper. I'll be doing that tomorrow. What's new. ? It was working then stopped. Customers are unhappy with the product's fuse issues. gui_tarzan Posts: 607 Joined: Thu Jan 16, 2014 3:10 am Location: The 26th State. A bulged cap is also not a good sign. Along with everyone else, I'd suspect the rectifier tube. If you want to reopen this topic, contact a moderator using the "Report Post" button. to/3SRSvMI☕ Buy Me a Coffee: https://buymeacoffee. Corona Posts: 60 Join date: 2010-03-11. com 303-955-2412. WOW! The music now has meat on the bones and a true quiet elegance to the sound that was hugely lacking with the stock PL 5AR4 version. This sounded exactly like a problem I had with my LoneStarSpecial when using the 5 or 15watts - blown rectifier tube. Thread Status: New power transformer and power supply can caps and a bunch of resisters at least. If this one is defect, the relais switch at 100hz and the fuse is blown. My guess is the rectifier tube shorted or one of the can caps. BUT, now that it’s dark outside and there’s less ambient lighting, I just happened to notice there’s no orange glow from the left rectifier tube (the SLI-80 has one rectifier per channel). I did not have any of this tube, so tried to replace it with a GZ34 (5AR4). It likes UF4007's. Replace. Old school rectifiers rarely wear out. Apart from the heater pins, which I won't need, the pins used are 3, the cathode; and pins 1 & 7, plates # 1 and 2. These tubes take a lot of "high voltage abuse". The power light on the amp fluctuates as I play and there is slight distortion when the amp is on 2 for volume. If you put the rectifier back in and it blows a fuse the next time you power it up its probably a bad A friend brought over his dual rectifier so we could do some recording with it, while we were setting up a tone I switched the tube/diode rectifier from diode to tube and the power mode from spongy to bold, as I did this the amp lost power, I'm not sure which switch caused this because I did one after the other, but either way I did it with the It also blew the rectifier tube (GZ34). dazzo; May 13, 2009; Tube Audio A rectifier is a part of the power supply in your amplifier. Post by Leo_Gnardo » Sat Aug Ever wonder how the rectifier tube's cathode survives after the amp is turned on but before the cathode (or filament) gets hot? People who operate broadcast radio and TV station tube transmitters do have to worry about cathode stripping. The Willsenton out of the box had a blown rectifier tube(RCA 5U4GB), so I swapped those out for a pair of Disconnect the PT secondary high voltage. The review from Positive Feedback is spot on and Before replacing the rectifier tube, measure the resistance from the rectifier tube cathode pin to chassis ground. Replaced the rectifier and everything is fine. Looks like it wasn`t just a blown rectifier tubeI replaced all rectifier tubes, got the amp working, but when I turned the standby switch on one of power tubes was glowing with blue color! I shut down the amp and ordered a pair of new power tubes. I have several components that it explicitly stated that I can use a variety of rectifiers in the same family: 5AR4, 5U4, 5Y4, 5Y3 etc. The 5Y3 rectifier tube, used in a Fender Tweed Deluxe, is a small rectifier tube that produces less DC voltage and thus exhibits more sag/compression. I quickly unplugged the amp. Even if a diode is blown, there will almost certainly be a reason for that elsewhere. 25 amp/3000V) on the plate and 1 W 470R(R64 & R61 1/4 W) resistors on input plate for output tube were smoked! Even burnt pcb under the 1 watter. Joined 2008. Cary SLI-80 with one blown rectifier TUBE HELP with 5AR4 Rectifier; Space-Teech Super Rectifier: Do I nee Pilium Alexander They are far cheaper than "vacuum tube" power transformers. photoenergy. This cap is probably not good anymore. Upon closer examination, the rectifier appears to be blown, or damaged, or something. Question for the more tube savvy among us – thanks in advance for your input if you have any. Your rectifier may have blown from the classic AC power interruption issue. I powered up my Cary SLI-80 integrated tube amp this afternoon, sat down, listened, and everything sounded great. A general question, more for my personal education. Iright now I don't have any diode installed and its back to its original wiring. The Amp is Completely Dead If the amp is completely silent (no speaker hum or hiss at all) then the problem can be just about anywhere in the amp but you I didn't think much of this either because it was the older fuse and I figured it just went. Link to Quality Vintage Tubes: https://valvesnmore. The amp turned on, popped fizzed, and Each tube is numbered, inside the bulb with a metal Tag; Hand blown, Globe shaped glass; Extra large getters. Jump to Latest inlet. I am assuming that the rectifier tube was damaged either due to the power cycling issue (hot restarts) or the line level thump. There was no sound after that so I put back the old GE SSE Blown fuse, arcing in rectifier tube. Diagnosing my blown-up tube amp. Try pulling out the 5U4GB (will only work in 90W mode, or 45W mode if set to diode on CH1 and CH2) and if the amp powers up then it is Rectifier related. If your amp uses tube rectification in its power supply, a shorted rectifier tube can cause a fuse to repeatedly blow. 9 KB · Views: 23 So I'm now pretty sure the faulty GZ34 had blown the resistor. Put one in series with each anode of the rectifier tube. There is no fuse. When I tried a new fuse it was OK for a few seconds then there was an arc in the rectifier tube and it blew its fuse. After blowing I have sound on only one channel but all the tubes seem to have the normal glow (lighting). and tried again with a new rectifier tube. Post by titser_marco » Wed Aug 26, 2015 2:14 am. Joined 2021. by photoenergy Fri Jan 17, 2014 1:09 am. by Corona Thu Apr 29, 2021 6:52 pm. IMG20240101115643. Post n°36; Re: RESOLVED - Rectifier sparked, fuse blew. " I put the new fuse in, and the amp works perfectly once again. I'm guessing I'll poke two diode cathodes into pin 3, and their anodes into pins 1 & 7, assuming they'll handle the voltage. Blown fuse and blown EZ80/6V4 rectifier in Cary SLP-94 Tried another and it blew also, but I noted one of the 5AR4 rectifier tubes flash purple at the same time. Replace the power tubes and the fuse, then try again. Like 1 Dislike. I will buy an old USED Mullard or RCA before buying a NEW JJ/Sovtek/Ruby etc. Plug in the AC cord, flip the power on and off, check the fuse. The B+ is the main operating voltage coming off the rectifier tube (which converts the AC from the power tranny to DC). sKiZo Posts: 1530 Join date: 2013-04-01 Location: Michigan USA. 1; 2; Next. I replaced the fuse, powered up, saw some If the fuse does not blow, replace the old rectifier tube with a new, known good rectifier tube. The GZ34S's two big metal plates are hollow in the center so the two cathodes (hollow tubes) will fit up inside them. [Eric] has an Atwater Kent 55C AM radio from the early 1900’s. Replace your rectifier diodes. I checked all KT88 and all tubes show 60% on my Heathkit TC2 tester. Happens Every 3 months or so. I'd wager that your power tubes have blown. Buy a couple of fuses and one tube. A few designs take the power from pin 2. The power tubes are Sovteks. Power the amp with the light bulb, both with and without the rectifier. FGub Posts: 6 Join date: 2023-09-02. Try a test with one rectifier and setup the output to produce 50 watts into a dummy load. Sometimes with a dual element rectifier just one half will go Amps with no standby either have a tube rectifier or a built in system to delay the full B+ supply from hitting the plate load resistors. If the fuse blows, take the amp to the doctor. Either are typically indicative of a power tube failure. Use clips on your meter. How to safely straighten bent vacuum tube pins and how to deal with a broken octal guide pin. Then try the other rectifier. Replace I was looking at 866a rec tubes and came across the 872-A Mercury Vapor Rectifier Tube. Does anyone know what the layout of the tubes are? Or maybe a link to something It replaced a rectifier tube that got broken during shipment" Read more. Reactions: dubadub and ElArte. If not, I'll just put 5. i have a cust Audiogon The world's largest high-end audio community. Tube noise such as sputtering, hissing, popping can be tougher to find in a guitar amplifier. I use my Mesa Triple Rectifier as the ultimate What type of fuse are blown ? Double check the rating. Your not going to save the planet with your miserable "green" attempts nor live much longer avoiding all the risks. I contacted my dealer who was happy to bring in a warranty tube but I had also emailed Upscale an initial query. wiuit zppt gymo utr evn obyrz ztdoh kue kxmhk dlbqk