[Amps] SB-220

[R.Measures]

>
>We're really hashing this one to death! 
>Needless to say, over 35 years of HR I still remember using the '220
>with a tube-operated HB 80-10 xcvr, and I worked CW (sans QSK, of course), 
>and SSB with no problems.
>
>After some experience in BC radio I liked to gently warm up filaments to 
>avoid sag as much as possible and that may have been the reason for the 
>inrush resistor. It's >25 years since and there's a lot of fish fried in 
>that pan.
>
>Whatever happened to AMP SUPPLY? 

***  Unsubstantiated rumour has it that the president of Amp Supply Co., 
Mr. Dennis Had was observed by his wife, during a surprise visit, doing 
some activity with his secretary on his desk at work, which led to  
divorce.  As a result, the company had to be sold in the community 
property settlement.  

>There's one model they made, the LK-500Z 
>that had three 3-500Z's. 

***  the LK-550?

>I added a grid current monitor board and a set of 
>nichrome parasitic chokes and that amp did real well. 

***  provided one has 200w to drive 3, 3-500Zs.

>I'd love to have one 
>of those again.
>
>Lastly, the stupidest move I ever made was selling my 77-Sx for $4K.
>There's another unit I'd spend the big bucks on. Dual 8877's and the amp 
>modified for grid control and parasitics: 5.1 KW if I wanted to be crazy, 
>but at 2KW it just loafed. Find me one of them and I'd spend the big bucks 
>all over again.
>
>The only facet of the '220 that I can remember as not too appealing was 
>the color scheme. 

***   The color of the Heath cabinet has been referred to as "puke 
green".  The reason is that simply viewing it can serve as an emetic for 
one who has food poisioning -- i.e.,  the offending food usually can be 
emitted by observing a Heath cabinet for about half a minute in a well 
lit area.  If the Heath cabinet can obviate a stomach pumping in an E.R., 
the 220 quite easily pays for itself.  

>Heath made a hell of an amp kit. It was worth every 
>nickel and it kept on working.

***  The cooling system was ingenious.   The design errors were minimal 
and easy to fix.  At c. 32¢ per pep watt, the value was great indeed.  
Updating and making the needed circuit improvements costs around $80.  
These are covered in:
http://www.somis.org/sb220ci.html
or in the Nov./Dec. 1990 *QST*.
>
cheers, Hal