SB-201/200 no output on any band

[Tom Chesek]

Thanks for the many replies. There are several ideas for me to persue when I 
get some time to jump back on that project. I'm anxious and curious to get 
it solved.

73,
Tom K3TVC



----- Original Message ----- 
From: "JF" <lhouseparker at LIVINGSTON.NET>
To: <HEATH at LISTS.TEMPE.GOV>
Sent: Sunday, October 19, 2008 1:42 PM
Subject: Re: [HEATH-TEMPE] SB-201/200 no output on any band


> Something to check: my 200 once suddenly had no output with nothing
> obviously wrong - turned out that one of the hard to see RF output line
> through-chassis bare wires had somehow come loose where it came through
> the hole from underneath and was soldered to its end point in the
> tube/tuning cap compartment. There are only 3 like that, all connected
> together under the chassis and emerging near the front: 2 are under and
> go to the LOAD variable cap, and the other is under the bandswitch where
> it connects to both sides of the rear portion and then via a bare wire
> to the rear of the 20/40/80 meter final coil L7. Are any of those
> missing or unsoldered?
>
> As that is the RF output line your problem could very well be somewhere
> in there, but might also be elsewhere. I would suggest pulling the
> chassis out of the cabinet and going through all the assembly steps in
> the manual, verifying the continuity & soldering of each wire and
> placement of each part, especially the bandswitch connections, as you
> say it was replaced and it would be easy to get connections wrong.
>
> If your 200 once had any arcing from parasitics (or in the one the
> replacement bandswitch came from) some of its contacts may have been
> damaged or vaporized, and if so may be hard to see. You can't get your
> fingers into the bandswitch while everything is installed, so you
> would have to take it out for a real inspection, something only a
> dyed-in-the-wool Heathkit fanatic would love. You might be well
> advised to start looking around for another switch.
>
> 73
>
> John F.  KE5ZB
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> Tom Chesek wrote:
>> I have an SB-201 which was converted to an SB-200 equivalent with a 
>> complete
> > bandswitch swapout. I cannot tell you if it ever worked after the swap.
> > This amp has the Harbach power supply mod and antenna relay including 
> > the
>> I've tried drive on each band from 30 watts to 100 watts with no output
> > measured on the amps' meter or on the watt meter inline to the 50 ohm 
> > antenna
> > load.
>> Tom K3TVC
>
> -----------------------------------------------------------
> Products bought, sold or traded here is the responsibility of the
> parties involved.  This list and the City of Tempe are not responsible
> for losses or misrepresentations of any kind.  Buyer beware!
>
> -----------------------------------------------------------
> This list is a public service of the City of Tempe, Arizona
> -----------------------------------------------------------
>
> Subscription control - http://www.tempe.gov/lists/control.aspx?list=HEATH
> To post - HEATH at LISTS.TEMPE.GOV
> Archives - http://lists.tempe.gov/archives/HEATH.html
>


--------------------------------------------------------------------------------



No virus found in this incoming message.
Checked by AVG - http://www.avg.com
Version: 8.0.173 / Virus Database: 270.8.1/1732 - Release Date: 10/18/2008 
6:01 PM

-----------------------------------------------------------
Products bought, sold or traded here is the responsibility of the
parties involved.  This list and the City of Tempe are not responsible
for losses or misrepresentations of any kind.  Buyer beware!

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.aspx?list=HEATH
To post - HEATH at LISTS.TEMPE.GOV
Archives - http://lists.tempe.gov/archives/HEATH.html