Silver jubilee ceriatone clone on 2210!?

[sluckey]

I agree with VMS, based on the pic he posted that shows two blue wires connected properly. However, I jumped on your best pic, the close-up of the diodes and there's only one blue wire connected in that pic. That's very confusing and frustrating.

[VMS]

As I understand this, the red wire (above C37) is the other blue wire. He couldn't solder it to the old place.

[sluckey]

Makes sense to me. But the pic you posted showed both blue wires correctly connected while the pic I posted only has one blue wire connected. And all pics of the STBY switch show two blues. I guess the red splices to a blue underneath the board? There's been some soldering going on between photos.

[Andre Oliveros]

well one pic, the one with both blue wires side by side was when i finished the sockets, but when i was inspecting i found that blue wire was cold solder, and was not making contact, also i found that par of that cable was damaged ( ruber burned) so i re-cover the blue wire with a red, and connected it where i put the "green dot" in the pic for the porpouse of explain where i soldered now, to also know if im correct to connect that cable over there since it follows the same path as the other point "the 3rd green dot" wich now for some reason i cant solder over there, so resuming the old blue cable now is half blue half red, ill paint it for better understanding (color blue) , its correct sluckey that its the last pic, VMS its right soldered there because i could soldered it to nowhere else that seems logical, its ok where i soldered it now?, makes any difference?, if its correct, what are the readings that i should take?

thanks and sorry for the confusion sluckey and VMS

[VMS]

that seems logical, its ok where i soldered it now?, makes any difference?, if its correct, what are the readings that i should take?

I think it's correct.

Here is a pic to help you with your DMM. When you measure Plate, Screen and Bias voltages the black test lead goes to ground bolt.
Pin numbers are for power tubes.

I'll let sluckey explain the procedure, because my English is not so good and I don't want you to electrocute yourself again.

[Andre Oliveros]

im going to do the readings, but i was thinking in another solution, do you guys know someone in LA, a friend of mine is going this december 10, so i was thinking to ask her to take my amp to a tech over there, also how much would this repair cost aproximately, and how many time because i think she would be over there like 15 days. thanks


Dre.

[Andre Oliveros]

im not getting any readings, for pin 5, its in 0.00

[sluckey]

Read this entire thread again. You'll see what your next move should be.

[Andre Oliveros]

bias (white cable)? ill do that today, yesterday i went to late home i just did fast the things, also i fixed that blue/cable mod, now the cable is where it supoussed to with no mixed cables.

[sluckey]

bias (white cable)?

Yes

Disconnect that white wire from the board and just let it dangle in the air without touching anything.

Set your meter to the 200VAC position (that's two clicks clockwise of OFF position).
Connect the black lead to the chassis.
Connect the red lead to the dangling white wire.
Turn the amp on.

You should have between 50VAC and 100VAC. What do you actually measure?

[Andre Oliveros]

i measure 0.00 with a titling minus. this mean that my new transformer is bad?

[sluckey]

Yes. We reached that same conclusion back in April.

[VMS]

this mean that my new transformer is bad?

If you have checked your fuses and you have correct voltage on the primary side of the PT but nothing on the secondary side, then your transformer probably is bad.

[Andre Oliveros]

how do i test the transformer? ill like to know if i just spilled 150$ for nothing if so ill burn that haunted amp, not really, but ill like to know if its good because i found a place where sell a 2210 board PTP, and am pretty tired of looking for components, that i just want to know if the tranny its ok then i buy the board install it and forget about problems, since the board its one of the things that i havent change, and also knowing that the Choke, Ot, and preamp sockets are ok,

[sluckey]

GEEZ! WHAT DO YOU THINK WE JUST WENT THRU ALL THIS SHIT FOR? The transformer is bad. I don't think it was bad when you bought it. I think you killed it because you don't have a clue what you're doing. Accept it and move on. I'm done!

[Andre Oliveros]

well sorry if youre getting mad, everytime your answer seems to be a big problem to you, so why you bother to answer anyway? if i ask its to double check everything i read, and also im learning how to do it, if this bothers you in some way just dont answer to me anything, saying that i killed the transformer when i just have been doing what you guys say to me its kinda rude, im asking because the other guy put his hands on the amp, i want to know why if i spend money in a new transformer it doesnt work (maybe the guy killed it if so ill tell him to pay for it), i dont think i killed the transformer since ill be doing only what you  and the other nice guys tell me to try and do, so really im sorry if you misunderstand me, or you are just tired, or you just dont feel like help, if thats the case im sorry to bother you, but really no one its forcing you to write any answer to me, ill not just move on till i fix, and understand everything, doesnt matter if you help me or if i have to buy books or read everything online, sorry but i really want to learn, and no one has the authority to make me feel like i cant, because you didnt born knowing everything you know, you should try to be more polite or just ignore what i ask.
thanks anyway because people like you just make me want to try harder , and also for taking the time to help, sorry for any problem that i caused to you.

[sluckey]

No problems. Just tons of frustration. Someone killed that PT a long time ago. You didn't kill it because of any advise you got on this forum. That amp had the very same problem back when you posted the first thread in April. Didn't you initially install that PT? Regardless of who did it, it was installed wrong and the bias winding died as a result.

I know you were told this back in April. You ask for help, then don't believe the logical answers you get. That's very frustrating to the people trying to help you. Your PT is bad and you probably caused it. It's unfortunate, but it does happen, even with knowledgeable people. So, if you want to fix that amp you will have to buy another PT. I hope you get it fixed, but I really don't care if you do burn it. Either way, I'll stay out of your threads. I feel I've danced with the Borg far too long.

[VMS]

Just to make sure that the problem is not between mains switches and the PT primary, do these following measurements.

1st: Measure that you have the wall voltage between blue and brown.

2nd: Flip the mains switch on and measure VAC between orange and red wire.

3rd: Report the voltages.

[Andre Oliveros]

117 VAC in both

[VMS]

117 VAC in both

Those seem to be OK.

Next flip the mains switch on and take following measurements:

VAC between gray and blue at the standby switch.

VAC between pin2 and pin7.

Report voltages.

[Andre Oliveros]

between blue and grey 361 VAC

[VMS]

between blue and grey 361 VAC

This is good.

What is the voltage between pin2 & pin7?

[Andre Oliveros]

thats ok 6.3 VAC

[VMS]

Ok, so the transformer is not completely bad.

Are you 100% sure that you don't get VAC reading between white wire (disconnected from pcb) and ground bolt (where the green wires are)?

If so, then we have to use a different method to get the bias voltage.

Easiest way is that you buy a small 120V:6V transformer and wire this in reverse to heater supply.

Second choice is to use a similar circuit that is in Ampeg V4 amp.

Good news is that you probably don't have to buy a new PT.
 

[Andre Oliveros]

ill triple check readings in that cable today so we can be completily shure... but hey yes they are good news, however would you mind to tell me  how to do this what are you asking me and where can i find the transformer 120V:6V?

thanks man

[VMS]

however would you mind to tell me  how to do this what are you asking me and where can i find the transformer 120V:6V?

Check first. I'll tell you what to do after that.

[Andre Oliveros]

ok, ill do that again

[chabby-ao]

Hey - I know you said you loved the tone of the 2210 before it broke on you, but if you loved it you'll absolutely go nuts over that amp converted to a 2204.
Trust me I know as I just finished one and it only took me a few days.

I ended up using odds and ends I had in my shop, but I could have easily done it with cheap radio shack terminal strips as well. There's a complete layout and schematic at Dreamtone amps.com and the only thing I took off the 2210's preamp board was the bias pot. I also had to configure a full bridge rectifier like is one the 2210, but that's child's play. This amp rocks and has balls like Malcomb Young would want.

I can send you a picture if you're intersted. You see at least part of the problems with the 2210 series was by that time (or at least for that model) Marshall cheapened the preamp board making it very fragile and almost as bad as Fender Hotrod series boards. Unless you are very good with an iron and have one with dial settings, you can look crooked at that board and fry the weld pads. Maybe I'm old fashioned, but why rehab something that is so weak to start with? Even with radio shack terminal strips you can weld and unweld componets to your heart's content. Not only dies this render a more durable amp, but infinitely mortweakable and moddable.

Best of luck to you. I'd bet you money there's not a thing wrong with the transformers you have!!!! Believe me I've been there, I thought my 2210's trannys were toast too, but by looking at how much that board and amp have been messed with.............just saying.

[chabby-ao]

Plus don't forget that PT only puts out low voltage compared to some because it's designed for a full bridge rectifier. Stupid me I tried to use the normal 2204 hook up and couldnt figure out why the voltage was so low since I grounded the CT even. Doesn't matter........it's not the PT trust me. I've been excactly where you are with this amp. Just convert it to a far superior 2204 and if you think you like the 2210....just wait until you here it as a 2204.

Just remember to build a full wave bridge rectifier and it will put out at least 450VDC at the plates. That's where mine is running right now. Very few folks understand these 2210's until you've actually worked on one, they suck to work on. I've built and repaired quite a few amps and none were more challenging than the 2210. Not because it's that complex, but because there's so much going on with the preamp board, tracing it's exact problem is only for the best, most well equipped techs, which I'm not and it doesn't look or sound like you are either. Try the link below and build this exact amp and your problems will be over. Took me about 3 days to finish and another two to trouble shoot because I'm an idiot soemtimes.

http://www.dreamtone.org/pdf/NEW2204LayoutSchemBomDreamTone.pdf


Heck, when I was in your shoes working on the 2210...first I thought it was the choke, then I thought it was the OT...then I thought it was the PT. But then I got rid of that damn board after removing and testing the tranny's out of circuit to see they were most likley just fine...even though the PT's secondary HT's threw me for a lop at first because the voltage is designed for a full wave bridge only. Also the 2204 will save you on both preamp tubes and in my case power tubes as well as I converted to a 50 watt using only two power tubes.
I'm using all the original trannys and choke. I got rid of the reverb and the extra 2 preamp tubes. The 2210 is an okay amp, but nowhere near as cool and ballsy as a 2204. I also opted for a couple small tweaks to make the 2204 more ballsy that are available on the "ultimate JCM 800 website" just a couple different resistor values here and there.

Oh...and as a side note....I get 97.0 VAC from my white wire bias tap. I just cut the center tap and heat shrinked it off since it's not used for a full wave bridge. And don't even think you're going to ground that CT and use a half wave.
Nope, that tranny is designed specifically for a full wave bridge - I already made that mistake. Oh you get voltage alright, just nowhere near enough to power the amp. Must be full wave bridge. When I received my 2210 it had been modded enough to have it's board meesed up in places I still don't even know about. But funny how everything I thought was broken now works perfectly in my redesigned 2204, tranny's and choke included. Jeez...I thought it was everything from tubes to tranny's - those boards SUCK!!!!
I even tested the board and ohmed out the entire thing....never did find a problem with it-lol! That's why I say unless you are highly skilled and ready to be so frsutrated you want to throw the entire amp out the window, do yourself a favor. You'd be done by now and playing if you listen to me.

[Andre Oliveros]

ok, can you help me then? i pm you.

[VMS]

Hi Andre.

Is there a reason you don't check the bias voltage for me?

Anyway, if the bias winding really is dead then here are two options for the bias supply:


Option 1. The easy way:

http://www.el34world.com/Forum/index.php?topic=6512.msg83232#msg83232

if you choose this one, I can give you a picture where to solder the components.

 
Option 2. With additional transformer:

http://lenardaudio.com/education/14_valve_amps_6.html

Picture from lenardaudio:

[Andre Oliveros]

i did, i found this: 0.00 VAC, but its something weird, i spoke with the guy that replaced the transformer, he told to me that he tested that part with both sides (white cable) and (green cables) unpluged, and it use to give him something like 150VAC, but when he atached to the amp (the green cables) the 150VAC just drop dead. what do you think?

[Andre Oliveros]

ok would you please give me the pic where to solder i want to try that one, i think ill going to spend first this solutions.

[VMS]

but when he atached to the amp (the green cables) the 150VAC just drop dead. what do you think?

I don't know. Check those bias caps C35 and C36.


Here is the way it is done in JCM900:

http://www.el34world.com/charts/Schematics/files/marshall/jcm900_21xx_25xx_100w.pdf

[chabby-ao]

That white wire should go to at least a 100K resisitor then to the anode of a IN4007 diode. The place the white wire is attached is near the bias section of the 2210's board on the controls side near the green and orange wires goin to the 220K r's. You also need to remove that silver diode/cap looking thing labeled 546 in small black numbers as that part never existed on that board.

If I were you I'd completely scrap this project before you really do screw up your valuable trannys and stuff., Just gut it and build a 2204/2203. I converted mine into a 2204. Only difference is a full wave bridge rectifier - it was painfully simple to do. That 2210 PCB board is tough even for very good techs- junk it!

here's some cell phone pix-its not pretty but sounds killer. Made from scraps around shop.http://i5.photobucket.com/albums/y183/jogman/Mobile%20Uploads/DSC01243.jpg

Here's the full wave bridge rectifer put on an old organ terminal board that had a chunk broken off just the right size-lol!:
http://i5.photobucket.com/albums/y183/jogman/Mobile%20Uploads/DSC01244.jpg

[chabby-ao]

The amp isn't pretty because I had to make due with what I had between a piece of wood/terminal strips and part of an old organ board, it worked but is pretty crowded, especially on the organ board. But what's cool is it runs dead quiet and is the most quiet running amp I've ever built - who'd think?

Anyway you could even used the wired already in place on most the tubes.
Just gut the two on the end leaving you with 3x9 pin preamp sockets.
I made mine a 50 watter to conserve tubes for one thing.

If you use that dream tone PDF I sent you it will be easy. Hardest thing was removing the board. Don't even try to salvage the pots off the PCB board because they are extremely hard to remove.