[Hallicrafters] Bumblee Caps

[james.liles at comcast.net]

Good afternoon Roy:

The General instruments film caps have General instruments printed on the 
case and generally have a red plastic end cap.

The Bumble Bee caps on the band width switch look like any other Bumble Bee 
but are 10% caps.  Others or all may be non-inductive but the bandwidth 
switch and timers in the radio definitely used non-inductive caps.

The SX-117, SR-150, HT-44, SR-400, SR-400A, and SR-2000 used the General 
instruments film caps for critical circuits relegating paper caps to 
history.

Go to www.k9axn.com, Service notes, Index, and view Notes 22, 23, and 24 for 
a comprehensive narrative regarding capacitor selection, why, and how to 
test your stock.  The tests require a grid dipper, VTVM or FET VM, and some 
common things found in any Ham shack.  I believe you will find the tests 
conclusive providing you with the information needed to make the appropriate 
selection of capacitors for the circuit that you are working with.

BTW, Roy, what level SX-100 are you working with; the 1a, 2, 2A, or 2B?

Kindest regards Jim K9AXN


-----Original Message----- 
From: Roy Morgan
Sent: Sunday, November 04, 2012 10:28 PM
To: hallicrafterssr2000 at k9axn.com
Subject: Re: [Hallicrafters] Bumblee Caps


On Nov 3, 2012, at 12:11 PM, <hallicrafterssr2000 at k9axn.com> 
<hallicrafterssr2000 at k9axn.com
> wrote:
> The SX-100 and other early 50Kc I.F. systems used 10% non–inductive  (High 
> quality?)Bumble Bee caps on the band width switch.  I have not  found a 
> single one of those caps that were within measureable  tolerance due to 
> leakage.

Thanks for the tip.  I have an SX-100 here to restore and another one
to follow that.

> ...General instruments non-inductive Polyester, not paper caps,...  have 
> the General instruments logo.

What does the logo look like?

> ... BTW, all of the Hallicrafters radios used non-inductive caps in  the 
> 50Kc bandwidth selection circuits.

Are they marked differently in some way?

Roy

Roy Morgan
k1lky at earthlink.net
K1LKY Since 1958 - Keep 'em Glowing!