Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kagliostro on November 24, 2011, 04:55:39 pm
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Today I discovered that Aiken amps have turret board on supports that usually we use for PCB circuits
see here (or google Aiken amps searching for images)
(http://www.amparchives.com/Amp%20Archives/Aiken/Aiken%20Intruder%2050%2050W/aiken14.jpg)
is this a good way to provide the circuit of a "shield" as to prevent noise and humm ?
often in RF PCB we can see that part of the unused copper is left on place as to use it as a sort of flat "shield", but is this useful also for our AF circuits ?
Kagliostro
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Today, if you make more than a few units, it is cheaper to have a "PCB" made than a "turret board", because EVERYBODY buys or makes PCBs and "nobody" works in turret boards any more.
The ground-plane is not a major feature. Hum and RF can be controlled with traditional techniques.
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It actually looks like it forms a capacitor to me?
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Thanks PRR & EL34
I can understand the explanation from PRR
and also was thinking that something, like EL34 say, will happen
(don't know if this can affect or help for our purpose)
Kagliostro
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He used to design medical electronics, and has designed a lot of PCB's that were rather critical, so he knows electronics, and how to do it right. He has a section on his website (http://www.aikenamps.com/PCBorPTP.htm) about why he uses them, but as he puts it, PCB's that are well designed are good. Turret boards that are well designed are good. Bad design on either one is bad.
He uses the turrets on his PCB's because they make it easier to modify them. Makes sense to me. And yes, he runs his traces on the back, and uses the top as a shielding plane. It probably doesn't make a big difference - particularly in something as noisy as a tube amp - but it can't hurt anything either, and if you are going use a circuit board, well, why not? What he DOESN'T do is mount tube sockets, jacks, pots, or anything like that to the PCB. Basically, he is just lacing all his turrets together with the circuit board.
Personally, I like making circuit boards, so while mine are nowhere near as good as his (no plated through holes, single sided, etc.), I've still done something like that on my amps. I like what he says about the turret/eyelet board vs. PCB debate though. When amp builders are starting out and their production is low, they'll talk about how turret boards "sound better," or are "more reliable." But as soon as they get popular and need to increase their production, it becomes, "PCB's are just as good as turret boards." Which of course is true, as long as you design them right.
Gabriel
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It actually looks like it forms a capacitor to me?
Sure, so do the wires running next to the chassis. It's a pretty low value one, though.
Gabriel
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I've seen some one else on this forum do that with copper clad boards. Makes for a nice clean layout. I think it's cool.
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Hi JayB, They are a good way to build circuit boards and if you have settled on a final design and layout they are great but if you want to do any mods and need to cut traces and the traces are on the under side, means you have to remove the board to cut them and its hard to add components as well.They do look good :icon_biggrin:
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Hi JayB, They are a good way to build circuit boards and if you have settled on a final design and layout they are great but if you want to do any mods and need to cut traces and the traces are on the under side, means you have to remove the board to cut them and its hard to add components as well.They do look good :icon_biggrin:
That's the only reason I havn't done it yet. Every amp I've built for myself, I've modded it in some way. :icon_biggrin:
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It looks like Matamps does a similar turret board pcb style thing too.
I found this shot of one of their amps.
Their low powered heads I think are actually point to point style.