AR 4X Dust Cap Question

[shacky]

Do you have access to a capacitance meter? It'd be interesting to see how they measure.

No I do not. Will be happy to send these to you if you like. I'd be interested too. I had sent some old EPI caps to Carl once. They were still close in capacitance but ESR had gone up.

 

[shacky]

Ventilated dust caps are very common. Many AR's had them. They aid cooling.
Also many of the early AR-2 and 4's had those pots. They work fine and don't corrode. Factory must have run out of the one that are seen most of the time and used those. I had one set of early AR-3 that had those pots and the were original.
Ed

I don't beleive these were original. Narodow had hem and put them in when he recapped.

There's a good thread over on CSP on the vented cap/AR background. Other vintage AR's like 3, 3a, and 2 series had a port hole on side of VC area to vent back inside cab - so dust caps were sealed.