Discussion in '"Boat Anchor" & Classic Equipment' started by KL7AJ, Sep 28, 2017.
Very nice have fun with the HQ 170 maybe if you get a chance you could post a picture.
I can tell that I'm getting old. I've owned products under most of those names, except for KW Electronics, Sonar, Karadio, McMurdo-Silver, and Howard.
Most Hammarlund receivers tend to be "drift city" especially above around 10 MHz including the HQ-100, HQ-110, HQ-160, HQ-170, and HQ-180 series as well as a lot of the Super Pro especially the SP-600 series. There are modifications that can be done, especially to the older Super Pro receivers, to eliminate a lot of this drift. Exceptions to this "drift city" do exist and there are individual receivers that are relatively stable.
However, the series that started with the HQ-120, then HQ-129X, HQ-140X, and ending with the HQ-150, are very stable after around a 15-minute warm up. With my original HQ-140X using a W2JAV terminal unit and a Model 15 Teletype machine, I could put the receiver on the old Reuters' New York to Havana radio link, walk away, and come back hours later to "perfect" copy of page, after page, of news information. Such took a very stable receiver.
My present HQ-140X is just as stable as my original unit.
There's a call from the past W2JAV Phil Catona was the President of our radio club and recall him giving a great RTTY presentation at a club meeting would not be a stretch to call him Mr. RTTY.
The 170 is prone to Silver Mica Disease in the IF cans and there are a ton of them and a PITA to replace, I use a 180, which is the general coverage version but otherwise the same, and replace as needed and have several other radios for general listening when s**t happens
They both eat the 6C4 oscillator which really needs a few mods to settle it down; drift and low end of a high range crapping out being quite common.
I have one in use on 80m regularly doing CW.
I have not found any drift trouble with mine yet after using it a few yrs.
They are pretty nice for both fone and CW, about on par with the Collins of the day.
Enjoy it before you tear into yours... don't think I would esp if you are doing just AM.
I cleaned up a 170 here a year ago or so and used it for several months for AM. Didn't do more than a little SSB listening, but didn't notice any significant drift after a few minutes warm up. Nice receiver.
OZU; That's a great specimen! Mine has more use wear of the lettering. Clock works but adjustment rod MIA.
I've found by experience of my screwing things up that it's best NOT to "fix" something that is functional.
Total Recapping comes to mind.
I really think it's an over-rated practice that is unnecessary in most cases, especially when said rig functions as designed.
Power supply filters though are a different story.
When there are paper capacitors involved, the unit may seem to work fine. But, when those capacitors are replaced, in almost every case the performance is definitely improved!
Also, paper capacitors are a time bomb waiting to go off. When they do short, or become extremely leaky, the situation may result in a lot more damage including wiping out very hard to replace (read very expensive) parts.
Just to amplify what Glen just told you, paper caps are virtually never used in RF circuits. They are typically used for audio coupling and bypass. So changing them out normally won't upset alignment. And you will avoid the eventual random failure. When one goes, it can easily take a tube and other parts with it due to high current draw.