[Hammarlund] HQ-170 Repair Saga

[manualman at juno.com]

On my HQ-170 schematics, C128 is connected to one arm of the noise
limiter control and not between T1 and T2.

 There are dashed lines around the transformer area of T1 and T2. Items
inside the dashed lines are in the transformers.
The coupling cap that connects one winding of T1 to one winding of T2 is
C134,  a silver mica, 2pf capacitor. Physically that is a very small
capacitor.

C134 is NOT in the T1 and T2 cans. However, the capacitors that are in
the cans can dialog into an additional story.

Pete, wa2cwa
www.manualman.com

On Fri, 3 Apr 2026 13:16:56 -0500 "Elmore, Kim via Hammarlund"
<hammarlund at mailman.qth.net> writes:
> 
> I need the expertise of someone with some deep HQ-170 repair 
> experience 
> to tell me where, physically, C128 is located. It's the coupling 
> capacitor between T1 and T2 and, if shorted, would short B+ to 
> ground 
> through R9. I'm beginning to wonder if it's *inside* either T1 or T2 
> 
> because under the chassis I see only a straight wire connecting the 
> two. 
> It's not shown that way on the any of the four versions of the 
> schematic 
> available and I can't imagine why Hammarlund might have done that 
> *unless* T1 or T2 were specified that way.
> 
> 73,
> 
> Kim N5OP
>