[Hallicrafters] 101 cap follow up

[Jim Liles]

Good morning:

All of the schematics that I have SX-96, SX-101M1, SX-101M3, SX-100M1a 
indicate ceramic disc caps.  They also have suffixes ranging from b to d or 
2 to 3.

The original question was should the sub-chassis be removed to replace any 
paper caps and or to test the components.  My opinion was no because the 
components can be tested from tube pins or external connections with the 
exception of capacitive values and the capacitors being Ceramic not paper 
could fairly safely be assumed good.   Yes, there are exceptions but I 
believe you will have to find a more valid reason to remove that sub-chassis 
than it might have paper caps which have to be replaced.  Would you clip the 
leads on Ceramic bypass capacitors elsewhere, simply to test them?

A follow on question was did any of the 50Kc sub-chassis assemblies after 
the S76 use paper caps?

I cannot see any way that seven paper capacitors could have been stuffed in 
the sub-chassis; four .02uf 500v and three .01 500v caps.  As I previously 
wrote, look at the S-76 which has but two paper caps in the sub chassis and 
how packed it is and add five more.

if you are courageous, you could get a tall one from the fridge, place the 
caps in or around the sub-chassis and drive your pickup truck loaded with 
concrete over it, then reinstall it and see if it works --- then sell it on 
ebay as a parts radio that worked 30 years ago when you packed it away for 
storage  --- NO returns.  I often thought of that years ago when I was 
trying to reduce the size of an electronics design --- still have nightmares 
about it.

The schematics were simply marked incorrectly indicating paper caps.

NOTE:  If you review the schematics from the HT-44, SX-117, SR-150, SR-400, 
SR-2000, etc, etc, etc you will find them laced with capacitors that are 
referenced as PAPER.  Not one of those caps are paper.  They are all Film 
caps and no they have not deteriorated like paper caps.  They are actually 
high quality General Instruments caps used mostly in critical circuits where 
stability is of the essence.

Kindest regards Jim K9AXN
We are not a democracy. We are a Constitutional republic with democratically 
elected representatives. THE CONSTITUTION IS THE INSTRUMENT MEANT TO PROTECT 
US FROM OURSELVES.


--------------------------------Original 
Message---------------------------------------------- 
From: Walt Cates
Sent: Tuesday, January 15, 2013 9:32 AM
To: hallicrafters
Subject: Re: [Hallicrafters] 101 cap follow up

Early versions of the 101 the caps in question were listed in the parts list 
as .01uf 500v 10% molded paper. In later MK series they are listed as .01uf 
+60-20% 450v ceramic.

Best Regards, Walt Cates, WD0GOF, 
http://www.myhamshack.com/WD0GOF/<http://www.myhamshack.com/WD0GOF/>
Only when you take full responsibility for where you are in life will you be 
able to find peace and joy in life.
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