[Hallicrafters] Re: HallicraftersV24#23- Black Beauties = Tiny Chiefs

[Phil Barnes-Roberts WA6DZS]

hallicrafters-request at mailman.qth.net wrote:
> Subject: [Hallicrafters] Re: Question about Black Beauties and Tiny Chiefs
> From: "Ken Kaplan" <krkaplan at cox.net>
> Date: Thu, 19 Jan 2006 00:27:21 -0700
> To: "Steve & Sharon Nordentoft" <sskn at msn.com>, "hallicrafters" 
> <hallicrafters at mailman.qth.net>
> 
> There should be a lot more than one Black Beauty. Mine had 22! Go to 
> http://www.qsl.net/kb7rgg/radio/index.html aand look toward the bottom of the page for a 
> couple of links. I don't know about the Tiny Chiefs. Are they those pinkish caps that look like 
> large micas?
> 
> 73 Ken kb7rgg
> 
> 
>>Hi to all Halli fans!
>>
>>Just a question for the wise.  
>>After just acquiring this fine SX100 from family and after I took a good look at it, I believe the caps are full of Tiny Chiefs and at least one Black Beauty.  Would someone please confirm my worst fear- that I should replace those caps since they are prone to disastrous failure?  I know the black beauties could be "death" to a radio and I think the tiny chiefs (very pink in color) are in the same league.
>>
>>Thanks!
>>STEVE
>>KA0BMQ
> 
To revisit this topic yet again:

The tubular paper capacitors, sometimes waxed brown paper tubes with 
printed markings, sometimes cast in black or red or green plastic 
shells, and either printed or color-banded ("bumble-bee" style) are all 
equivalent.  Sprague made many of the black ones, branded Black Beauty, 
and another maker (Cornell Dubilier) branded their red ones Tiny Chief, 
black and green ones Black Cat, and likely a few other brands, but they 
look otherwise much alike.

There are unfortunately even a few rectangular papers that look a bit 
like the molded micas (but the real micas are likely to outlast most of 
us.)  The first dot on the domino markings should identify the type; 
silver is AWS Paper, per decoders like < 
http://www.pc-control.co.uk/capacitor_codes.htm >.  Google [capacitor 
code] for several of these tables.

Also unfortunately, there are many vendors (including on <that auction 
site>) who will happily sell you a NOS=New Old Stock paper cap, of any 
of these brands, for $4-to-10 (or more!) each.  Guitar-amplifier users, 
and a class of enthusiasts dubbed "audiophools" are especially targeted 
by these folk, extolling the "warm tube sound" of the Real Original 
Paper caps.  A lot of the "warm" part will come from your power supply, 
frying, as the years of moisture infiltration causes the acid-made paper 
to leak and draw more and more current, throwing biases off until they 
fail catastrophically.  Google ["tiny chief"] (with quotes) for an 
eye-opener to this monkey business.

Replace them (one at a time, checking as you go) with most any of the 
mylar, polypropylene, polyester, etc. caps available now.  Several of 
the antique-radio sites can supply modern caps, like the "orange drop" 
radial styles and little yellow axials, fortunately usually smaller than 
the old papers.

In the capacitances less than electrolytics, (say 1uF or less), a common 
voltage rating like 630VDC is just fine, and not overkill.  Vendors like 
< www.justradios.com > can even supply older values, in inexpensive kits 
good for doing several radios.

Several sites (Google [recapping radio]) have more detailed instructions 
on selecting and replacing these caps.  Don't forget the electrolytics; 
both power-supply filters and things like cathode-bias bypasses can dry 
out over time, and cause trouble; hum in the audio, very low audio (the 
bypass isn't there, so there is negative feedback across the 
cathode-grid circuit) can result.  If you suspect this, bridge with a 
new cap of sufficient or comparable voltage rating, and see if that 
helps.  If so, replace it.  Often, you can leave a chassis-mounted can 
in place, just disconnected, and put new parts underneath, out of sight.
-- 
73, Phil Barnes-Roberts WA6DZS mailto:wa6dzs at arrl dot net
All else aside, RF to the other fellow's antenna is what counts.