Point to point or use a PCB

[jarthel]

well traditionally, tubes circuits have used point to point.

Well it's ugly for me and hard to "debug" if there are problems in the circuit. Is it possible for me to use a PCB for th resistors/caps and other parts and connect the respected points to the tube pins using wires? Any negative effect on using a PCB?

Thanks for the replies.

Jayel

 

[dhaen]

Why not? Lots of commercial designs use PCB's. Not because they're easier, but because they're cheaper in quantity.

Debugging? A hell of a lot easier with P2P!

Downside? Longer cables with PCB's. Some say that's a problem.

Cheers,

 

[jarthel]

Debugging? A hell of a lot easier with P2P!

This is subjective and since I've built circuits only on PCBs/breadboards for the past 10 yrs, it's easier for me.

Downside? Longer cables with PCB's. Some say that's a problem.

any explanation on the downside?


thanks for the replies.

jayel

 

[Tube_Dude]

To loooooong.....

any explanation on the downside?

As tubes are high impedance devices ...long cables are more prone to noise and hum pickup...

 

[jarthel]

what if I twisted pair (the other wire connected to ground) for every wire going into the tube socket pins?

I guess this would help. right?

 

[dhaen]

Not sure where this is going..

Originally posted by dhaen:
Debugging? A hell of a lot easier with P2P!

This is subjective and since I've built circuits only on PCBs/breadboards for the past 10 yrs, it's easier for me.

Well, I have found considerable difficulty moving PCB traces

Seriously, it is possible to get a better job all round with P2P.
Oh, and in case you think I'm a luddite, and not "PCB aware", here's one of mine:
Here's one of mine (not valve though)

Cheers,

edit: typo corrected.

 

[dhaen]

what if I twisted pair (the other wire connected to ground) for every wire going into the tube socket pins?

I guess this would help. right?

Not at all; Possibly the worst thing you could do. High impedance circuitry is sensitive to even small capacitance.

Have a look at the pictures of kit built by others to get some idea of the best (established) techniques. You are unlikely to better them, until you gain considerable experience yourself. So you may as well follow them.

Cheers,

 

[pedroskova]

Why not a P2P breadboard, and a PCB final? I'd keep ground P2P in the final since you're more apt to run into unforseen problems there than anywhere else.

 

[Bas Horneman]

Oh, and in case you think I'm a luddite, and not "PCB aware", here's one of mine:

John, I'll show you mine if you show me yours type behaviour is really not acceptable anymore these days

What on earth was that for?

Cheers,
Bas

 

[dhaen]

John, I'll show you mine if you show me yours type behaviour is really not acceptable anymore these days

What on earth was that for?

Cheers,
Bas

I know it's Friday, but there's no point getting frisky


It's one of these......Blatent advert for someting no one on the forum would want

Cheers,

 

[fdegrove]

Hi,

P2P or better still C2C.

Friday or not...over and out.

 

[Wardsweb]

There is no written rule you have to use all of one or the other. Many kits (like Consonance) use both topologies and they sound fine.

 

[jcarr]

Wardsweb: Agreed. Analyze each circuit node for what kind of operating conditions it wants (constant impedance, low capacitance, shielding etc.), and give it a suitable environment.

I primarily rely on four-layer pcb construction (including ground and power planes), but add special structures (isolated stand-offs, p2p, floating isolated pads etc.) wherever appropriate.

hth, jonathan carr

 

[EC8010]

Whichever you like

I use PCBs and P2P. They both have their advantages. PCBs can be good for RIAA stages because a double-sided PCB allows a ground plane. In the end, my choice is usually enforced by the components I want to use - some are designed for PCBs, others for P2P.

Downside for PCBs is the poorer dielectric (FR4 vs air).

What's far more important is careful layout...