[Heathkit] SB-610 focus issues

[Chuck Penson]

Thanks, Pete.  Very helpful. 

Best,

Chuck / WA7ZZE

> On Sep 28, 2014, at 4:05 PM, <manualman at juno.com> wrote:
> 
> Chuck:
> Count yourself lucky you have one SB-610 that doesn't have an astigmatism
> problem with the trace. Even though you have checked all related
> components, I would checked them all again especially the resistors. Some
> resistors will change value when current is flowing through them. If
> they're the original resistors, I would replace them. Also consider
> adding an astigmatism control similar to what's in the SB-620 or SB-614.
> If I remember correctly, both of my SB-610's, HO-10, and HO-13 all now
> have an astigmatism control.
> 
> Pete, wa2cwa
> 
> On Sun, 28 Sep 2014 15:50:39 -0700 Chuck Penson <wa7zze at gmail.com>
> writes:
>> Thanks, Glen. The 610 in my main station does not exhibit this focus 
>> problem. It is sharp from end to end. The 610 on my bench is another 
>> story.  I have not seen this trouble on several IO-21s that have 
>> passed through my shack. They were all sharp. 
>> 
>> Curious. 
>> 
>> Chuck / WA7ZZE
>> 
>>> On Sep 28, 2014, at 3:33 PM, Glen Zook <gzook at yahoo.com> wrote:
>>> 
>>> Very common with the SB-610!
>>> 
>>> One can get a "so so" focus across the entire line.  But,
>> definitely not sharp.
>>> 
>>> Glen, K9STH 
>>> 
>>> Website: http://k9sth.net
>>> 
>>> 
>>>> On Sunday, September 28, 2014 5:10 PM, Chuck Penson
>>> <wa7zze at gmail.com> wrote:
>>> 
>>> 
>>> Hi, all;
>>> 
>>> I've got an SB-610 that works great but the trace goes out of
>> focus at the far ends. So, good in the middle and not so good at 
>> either end. One end or the other can be brought into focus but then 
>> the middle goes out of focus. 
>>> 
>>> Have checked all the focus related voltages and components. 
>>> 
>>> Any ideas?
>>> 
>>> Thanks!
>>> 
>>> Chuck / WA7ZZE
>