Members t_e_l_e Posted December 20, 2015 Members Share Posted December 20, 2015 i just was in our rehearsal space and wanted to fire up my BYOC tweed royal (tweed deluxe/champ clone), which worked very well on thursday. after turning it on and from stand by to really on, there was no sound at all. no crackling no hiss no hum, nothing. i had a look at the tubes, they all to seem glowing fine, except the rectifier tube. should a rectifier tube glow aswell as to others? it did not became warm or anything. is this already the sign it is blown? any other ideas how i can get sure before buying a replacement? any idea what could happened that the rectifier tube is gone, while it was working on thursday? supposed nobody else was in the rehearsal room in between, i need to clarify this with our drummer first Link to comment Share on other sites More sharing options...
Members Tomm Williams Posted December 20, 2015 Members Share Posted December 20, 2015 My answer might not help much but the rectifier tube on my deluxe reverb glows just as brightly as the power tubes. I can't speak to anything else. Link to comment Share on other sites More sharing options...
Members onelife Posted December 20, 2015 Members Share Posted December 20, 2015 There's not much that can go wrong with a rectifier tube. It either rectifies or it doesn't. It should glow and heat up like the other tubes. It usually has its own filament supply coming off the power transformer. The problem may be with the supply or the tube. The quickest way to check (if you have access to one) is to swap with another tube. If not, you can open up the amp and (carefully) measure the filament voltage between pins 2 and 8 on the rectifier socket. There will be HIGH VOLTAGE on the tube socket so, if you are not confident working in that situation then use the tube swapping method to test. Link to comment Share on other sites More sharing options...
Members Mikeo Posted December 20, 2015 Members Share Posted December 20, 2015 I'm not guessing to tell you it's not the rectifier tube and I'm not guessing to say it is. If the rest of the tubes are lighting up, I think it's ok, you need to look under the hood. You'll need a DVM and some nice test leads. Alligator clip test leads.The schematic is online and there's some test points you will want to look at coming off the rectifier. Pretty high voltages so be careful and work with one hand in your pocket , as they say. All the tubes should glow, so who knows. Even with a bad rectifier tube, the power tubes will glow a bit on the filament. byocelectronics.com/tweedroyalinstructions.pdf Link to comment Share on other sites More sharing options...
Members t_e_l_e Posted December 20, 2015 Author Members Share Posted December 20, 2015 thx for the first answers, it helps to know that the tube should be glowing, which it is definitely not.i did check the schematics, cause the thought came to my mind that the fuse could be blown.but from the schematic this is impossible, cause if the fuse would have been blown, the light of the amp and the other tubes would not glow. so just from the analysis without any measuring now, this narrows it down, that the rectifier tube is gone, or there is something wrong with the secondary wires for the rectifier tube from the power trany, cause the primary is at least working for the rest. so hopefully the tube. do they also blow from time to time, like the other tubes do, or is there a special reason why such thing happens? stock is a JJ 5y3 in there, any recommendations for a replacement? would different models have different affect on sound? Link to comment Share on other sites More sharing options...
Members onelife Posted December 20, 2015 Members Share Posted December 20, 2015 Any vacuum tube will have problems if air gets into it. It's possible the rectifier leaked and, as a result, the filament burned up. Link to comment Share on other sites More sharing options...
Members Tomm Williams Posted December 21, 2015 Members Share Posted December 21, 2015 Between the tubes or wiring/related components, I would have to believe the odds of the tube failing would be much higher. Of course definitive testing is in order. Too bad you don't have a spare tube as a quick check. Link to comment Share on other sites More sharing options...
Members t_e_l_e Posted December 21, 2015 Author Members Share Posted December 21, 2015 Between the tubes or wiring/related components' date=' I would have to believe the odds of the tube failing would be much higher. Of course definitive testing is in order. Too bad you don't have a spare tube as a quick check.[/quote'] i have spare tubes, but not a rectifier tube, cause this is my first amp with such and its the first time failing, therefore i also asking those questions for the first time. i'm off now for christmas to the family, so this needs to wait after the holidays anyway Link to comment Share on other sites More sharing options...
Members WRGKMC Posted December 21, 2015 Members Share Posted December 21, 2015 Having the other Tubes light up is no indication the rectifier is working. The tube are heated directly from an AC filament tap off the transformer.I'm guessing you would have checked the speaker cable. Hopefully you aren't doing something foolish like running a cab with a guitar cord which can overheat and go bad. The rectifier tube provides the high B+ DC voltage and when the tube goes bad you get no sound.If the tube isn't lighting, and doesn't heat up either it may be the Rectifier filament blew.Best thing to do is just change it. In fact if the tubes are old it may be time to do them all. Keep in mind many amps with standby switches have a B+ fuse. If the transformer sees a heavy load the fuse opens and removes the B+ transformer wind. The filaments may have their own fuse, or may be protected by the mains fuse. Just depends on the amp. If changing the tube doesn't fix the problem, You can have a blown power transformer. The symptoms will be identical.Shorted power caps can take out a power transformer. All of these should be checked as a matter of course. When tubes start blowing,9 times out of 10 you have additional issues going on. Even if the tube gets you back up and running, you should visually inspect the power caps first to see if they have any bulging at the relief valve. There's a dimple at the positive end which prevents them from exploding. If the dimple is bulging out or has any while electrolyte leaking, change the caps immediately. Caps can leak and still function intermittently but inside they may be arcing between the plates. A shorted cap can take out the power transformer and cause the same symptoms of no sound, but since the filament wind is usually in series with the high voltage wind. Having filaments lit is a good sign the transformer is still good so check your power caps, fuses and replace the Rectifier tube. Then when you power up keep your eyes on the power tubes. If you see any abnormal red cheery glow, power down and get the power tubes replaced and properly biased. When the power tubes glow red its a sign the grid/screen resistors may have opened up. These resistors are usually connected to the bottom of the tube sockets. Inspect when while checking your power caps. Power tubes can blow like this if your amp isn't running the proper speaker impedance load. If you are running extra speakers with the amp, be sure they match the heads impedance rating. Improper loads on solid state gear tend to blow out quickly but with tubes the damage may be slow taking months before they blow. The damage may not be recognized as load imbalance and people may not correct the problem and have the same issues again. Link to comment Share on other sites More sharing options...
Members Tomm Williams Posted December 21, 2015 Members Share Posted December 21, 2015 WRGKMC Towards the end of your post you speak to the tubes glowing red indicating an issue. What exactly are you saying as the tubes in all my amps glow red. I'm guessing it's to a higher level ? Link to comment Share on other sites More sharing options...
Members onelife Posted December 21, 2015 Members Share Posted December 21, 2015 I believe he is referring specifically to the plate of the tube glowing red. The filament near the pins will glow when the tube is operating normally. The plate usually runs the length of the tube so the glow, if it overheats, will appear more in the middle of the bottle. Link to comment Share on other sites More sharing options...
Members Tomm Williams Posted December 21, 2015 Members Share Posted December 21, 2015 I thought so too but know enough to know I don't know enough. Link to comment Share on other sites More sharing options...
Members WRGKMC Posted December 22, 2015 Members Share Posted December 22, 2015 Onelife nailed it. Instead of just the filaments lighting in the center of the tube the outer metal plates of the tubes heat up and glow cherry red. This rarely lasts very long before the fuse or transformer blows. There will be no sound of course at that point and its usually preceded by the grid resistors blowing. Resistors have a distinct smell which ligers for a long time in the chassis when the outer Bakelite coating smokes. Using your nose is simply another tool for knowing something is fried. Link to comment Share on other sites More sharing options...
Members ToneMonster710 Posted June 27, 2020 Members Share Posted June 27, 2020 FOR Member: WRGKMC or anyone else that has in-depth knowledge about rectifiers and fuses. I have a SUPRO 1650RT ROYAL REVERB 210 COMBO AMP Bought it used - No warranty so I need help in fixing my RECTIFIER problem on my own. FYI - I have the 35/60 TOGGLE SWITCH Version giving the user the choice of 35 watt A amp, or 60 watt AB amp, not the "knob" version that switches from 35/45/60.ALSO - BOTH VERSIONS of the Supro 1650RT have DUAL Rectifiers. a digital rectifier for the 60 watt AB section of the amp, and a TUBE rectifier for the 35 watt A section of the amp.It seemed that everything worked. The "cleans" on this amp are amazingly sweet and chime nicely. I do get minimum breakup from the 60 watt section with digital solid state rectifier BUT NO BREAKUP AT ALL from the 35 watt tube section rectifier. I called the TUBE DEPOT and their tech dept says they are very familiar with the amp and said I need rectifier tube TO GET THE BREAKUP in the 35 watt position.I bought two New Rectifier tubes just in case and I plug one in AND NOTHING. tube doesn't light up or get warm in anyway - I thought maybe a bad tube fluke thing.I plug in the other and the same thing so I read YOUR take on this which you posted 5 yrs ago. You Wrote: "The rectifier tube provides the high B+ DC voltage and when the tube goes bad you get no sound. If the tube isn't lighting, and doesn't heat up either it may be the Rectifier filament blew. Best thing to do is just change it. In fact if the tubes are old it may be time to do them all. Keep in mind many amps with standby switches have a B+ fuse. If the transformer sees a heavy load the fuse opens and removes the B+ transformer wind. The filaments may have their own fuse, or may be protected by the mains fuse. Just depends on the amp. If changing the tube doesn't fix the problem, You can have a blown power transformer. The symptoms will be identical" I am thinking that since everything works on the amp except for no breakup on the 35 watt, rectifier tube side, and the new rectifier tube is just dead that maybe you are correct in saying that the TUBE RECTIFIER has its own fuse and its blown causing this whole situation? BTW - I also changed all the other tubes as well so this amp has 100% ALL new tubes. ANY LIGHT YOU OR ANYONE ELSE CAN SHED ON THE MATTER WOULD BE MOST APPRECIATED, Thanks in advance ... Link to comment Share on other sites More sharing options...
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