[Hammarlund] Seeking Guidance to Repair HQ-170

[Kim Elmore]

I'm still flummoxed.

The incinerated resistor value is 1 k and it is R9: it was incinerated 
after serving well (as far as I know) since 1959 when my dad bought the 
receiver, new. The original manual, in which he notated repairs and any 
mods, is lost. I have determined that Revision 2 of the manual and 
schematic apply to this receiver and I have these. Based on the 
schematic whatever caused R9 to burn up resides somewhere between T1 and 
T2. I need to check C134, a 2 pF coupling capacitor between T1 and T2 
but I simply cannot physically find it. While it's a long shot, I need 
to eliminate it as a cause (make sure it's not shorted) and I can't find 
it. I know what it should look like, but...

I've noticed in some images I see of the chassis underside (restoration 
pages, museum pages, etc.) R9 is clearly NOT original. This leads me to 
conclude that I'm not the first to experience this failure, but no one 
so far has apparently run across this, either. R9 is called out as 1/4 W 
and is on it's own single-lug terminal strip tat is riveted between and 
just to the right of T1 and T2 so as to avoid the array of trimmers that 
are the left of T1 and T2.

Any specific insights and experience with this particular failure are 
greatly appreciated!

73,

Kim N5OP

On 3/11/2026 8:12 PM, Kim Elmore via Hammarlund wrote:
> This is my first post to the group: I have an HQ-170 that has me 
> flummoxed. It's has been "in the family" since my dad (W5JHJ SK 2007) 
> purchased it new in May 1959. It, along with his WRL Globe Champion 
> 350, comprised the first station I operated as a Novice in Fall 1970.
>
> While I have a fair bit of experience working on the Champ, I have 
> very little with the HQ-170: it simply has never needed much. My dad 
> made no significant modifications to it aside from adding a modern 
> 3-wire cord, an I.F. out port, and a plug for the mute circuit. A 
> while back I turned on everything to let it warm up and was alarmed by 
> a burning-paper smell. The source of the burning-paper odor was the 
> '170. Upon removing it from the case, I discover half of an 
> incinerated 1/4 W carbon resistor sitting in the bottom. A brief 
> inspection reveals the other half remains soldered to a pin on T2, the 
> transformer just to the rear of the 6BE6 1st converter (V3). The other 
> side of the incinerated resistor is, or rather was, wired to terminal 
> strip that has a lead to a pin on T6 (immediately behind V5, the 
> second converter) that oddly appears to be vacant on the schematic. 
> The linked image shows where the incinerated resistor was, circled in 
> red. The resistor you see in the image is a out of my junk box and I 
> put it there only so I don't lose track of where the incinerated 
> resistor was.
>
> A link to the image is here: 
> https://drive.google.com/file/d/1wD4ZJ8Y8QhLlgcJzYyYHEObE5YwCNjAo/view?usp=drive_link
>
> I'm posting this in hopes that someone else has encountered the same 
> problem and can guide me to a proper repair.
>
> 73, N5OP
>
-- 
Kim Elmore, Ph

Kim Elmore, Ph.D. (Adj. Assoc. Prof., OU School of Meteorology, CCM, PP 
SEL/MEL/Glider, UAS, N5OP, 2nd Class Radiotelegraph, GROL)

/“Listen, it's too big a world to be in competition with everybody else. 
The only guy I have to get better than is who I am right now.” – Col. 
Sherman T. Potter, 4077 M.A.S.H./