[Hammarlund] Seeking Guidance to Repair HQ-170

[kgordon2006]

Hello, Kim, although I also own an HQ-170, I am not yet familiar enough with it to lead you directy to a solution for your particular issue.However, it has been my experience that when a resistor is damaged in the way yours has, the cause is usually a shorted capacitor associated with the circuit, snd usually it is a voltage -blocking capacitor. I would be checking any in the vicinity of that resistor before replacing it.It sounds to me as though that resistor is the source of plate voltage, or perhaps, screen voltage, to one of the IF amps.Ken W7EKBSent from my Galaxy
-------- Original message --------From: Kim Elmore via Hammarlund <hammarlund at mailman.qth.net> Date: 3/11/26  18:12  (GMT-08:00) To: hammarlund at mailman.qth.net Subject: [Hammarlund] Seeking Guidance to Repair HQ-170 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_linkI'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, PhKim 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./______________________________________________________________Hammarlund mailing listHome: http://mailman.qth.net/mailman/listinfo/hammarlundHelp: http://mailman.qth.net/mmfaq.htmPost: mailto:Hammarlund at mailman.qth.netList Administrator: Gary Harmon, K5JWK** For Assistance: gharmon at idworld.net **This list hosted by: http://www.qsl.netPlease help support this email list: http://www.qsl.net/donate.html