Stopping board sag?

[LeapFrog]

I have a few (older) radios that the pcb is starting to sag in, any fix for this?

 

[Robb]

A 'over-the-shoulder-boulder-holder chassis supporter?'
Not that I am aware of . . .

 

[LeapFrog]

I'm glad it's only two radios that have this issue, must have been stored in a damp/humid climate for some time.

 

[space cowboy]

put non-conductive supports underneath. pc's have supports under the boards. those are part of the grounding system though.

 

[loosecannon]

The Cobra 139XLR used to be plagued with cracking PC boards, and there used to be a kit you could buy that would include metal strapping and rubber/foam standoffs that would exert pressure on the board in order to keep in from shaking and flexing.

i imagine this concept could be applied to any radio, and a solution could be fabricated.

here is a link to the article (look at 'problem B'):
http://www.cbtricks.com/pub/secret_cb/vol_02/graphics/secret_cb_vol_02_pg45_50.pdf

LC

 

[Captain Kilowatt]

Pull the board and put a small block of rubber foam under it to stiffen it up.

 

[LeapFrog]

Thanks guys, all great ideas!

 

[wavrider]

VIAGRA
Get ya some VIAGRA,, whenever your OCD kicks in and you start stressing about a sagging board take one of those pills,
You will quickly forget about the sagging in your boards cause your woody is hard.

 

[LeapFrog]

If you cannot change it, ignore it!
Going to use "foam blocks and a bracket".

 

[space cowboy]

I don't know as I'd use foam. it tends to disintegrate over time not just costing you the support, but also giving you a case full of fine powder. my preference would be plastic or rubber.

 

[LeapFrog]

I don't know as I'd use foam. it tends to disintegrate over time not just costing you the support, but also giving you a case full of fine powder. my preference would be plastic or rubber.

20/20 hindsight, thank you space cowboy!

 

[Captain Kilowatt]

I don't know as I'd use foam. it tends to disintegrate over time not just costing you the support, but also giving you a case full of fine powder. my preference would be plastic or rubber.

That's why I said rubber foam as opposed to styrofoam or the like. Rubber foam is basically neoprene like material and will not disintegrate and go to powder.

 

[JoeDirt]

Could you cut strips of copper clad board, stand it up on end notch out some for clearance and solder it to the ground on the foil side in multiple locations?
____________________
|__-----___----____----___|

 

[Captain Kilowatt]

Sounds like a short waiting to happen.

 

[Robb]

Speaking of that, loosecannon posted that Service Bulletin that pointed out, not only do these boards sag; but as a major consequence this sag can/does make the board crack and traces break open. SO this can go from an annoyance into being a failing point that may need serious inspection of the trace side of the board and possibly needing repair.
Read it:
http://www.cbtricks.com/pub/secret_cb/vol_02/graphics/secret_cb_vol_02_pg45_50.pdf