Missing turret and bias issues...

[Twistingcrow]

Hi guys!
This is my first 100W build. I have built several JTM45s before. It's still blissful building those amps!

Anyway, I got my 1969 plexi kit about 10 days ago and I have just finished step 15. Except that one of the turrets on the board is actually missing (the last one to add a blue wire to before finishing step 15... This is the first time that one of George's kits gets to me with something missing... Obviously it will be the last...

But since I don't have turrets available I devised a hook to get there using 18 gauge buss wire. It's in the middle of the picture, right next to the purple wire. Here's how it looks:



Could you please tell me if this is going to be fine? Aesthetically of cousre it's not, but right now I'd just like to know if the amp will still work with this, or if I'm potentially damaging something with my invention...

Thanks guys!

[toner]

I suppose you could make it work but it will be tough mounting the components there. Two caps and a resistor connect at that point. If it were mine, I'd take the time to install a turret before finishing the amp.

[VelvetGeorge]

That's unacceptable! Very sorry about this.

We can build a replacement board or send parts to install the missing terminal, your choice.

george

[Twistingcrow]

Well George, I'm too lazy to unsolder everything and install a new board there! So unless it's too hard to do I'll choose the new material to install a new terminal there... I hope it's not too tricky to do...
As far as connecting more components there I know it's gonna be tricky, but I can't wait for George's stuff to arrive since I'm overseas. That would mean waiting two more weeks before finishing and playing the amp, and I can't do that, so I'll do my best!!! Unless you tell me that it's gonna harm the amp I'll do it!
Thanks,
Fred

PS: George, I'm shooting you a PM!

[Twistingcrow]

I suppose you could make it work but it will be tough mounting the components there. Two caps and a resistor connect at that point. If it were mine, I'd take the time to install a turret before finishing the amp.

No worries toner... It's just a momentary tweak. I just wanted to know if that would work until I receive George's stuff. I WILL install a turret there of course. I just hope that I won't have to pull everything out to install that ony single tiny turret there... And I hope it doesn't require tools I don't have...

[Twistingcrow]

Hi there guys!
The amp is complete and works despite that crappy invention. I have a slight problem though: my V7 is way hotter than the rest of the tubes. I set it at 36 mV whereas all he others are around 27mV with a 502V B+... 9 mV is a lot of difference! Do you think it could be because of that missing turret or do you think it's just an unmatched quad?

Thanks!

[elronhoover]

Hi there guys!
The amp is complete and works despite that crappy invention. I have a slight problem though: my V7 is way hotter than the rest of the tubes. I set it at 36 mV whereas all he others are around 27mV with a 502V B+... 9 mV is a lot of difference! Do you think it could be because of that missing turret or do you think it's just an unmatched quad?

Thanks!

Does the hi draw stay on the v7 socket if you swap power tubes around, or does it stay with that particular tube regardless of which socket it's in?

Dave

[Twistingcrow]

Thank you Dave. I've just tried what you said and swapped the V7 and V8 tubes. The problem is definitely the tube, because now V8 is at 36mA whereas the other tubes are around 26 mA... I don't have a matched quad at all here... 3 of them arematched but not the 4th tube...

George can you help? I guess you are very busy but I'm still waiting on you here with that ugly buss wire instead of a terminal and a faulty, unmatched quad of JJ's...

Thanks!
Fred