[Hammarlund] HQ 180 IF problems / mods

[Charles Ochs]

I have had one of these for the last 25 years. It has mainly been my bed side radio, and one of the best boat anchor radios for SSB reception. The fine tuning control, and the slot filter are pretty useful.

Having said that, however, it should be noted that this radio, like it's brothers in the line up, are far from the very robust radios that the SPs are.

By the time the '60s rolled around, the industry, in general, had begun to switch to those fussy little "K-tran" style IF cans. which, along with  all the other "coils" in the front end, has made these radios a nightmare to keep running.

Given the fact that "rust never sleeps", if you own one of these, EXPECT trouble--sooner or later if you haven't had it already.

As far as mods are concerned, none of the common mods--power supply, filament transformers, etc are worth the effort.

Solid stating the power supply brings with it a set of issues which are far too much trouble, and will give virtually NO improvement.

Even "widening" the audio will have little effect, as the IF passband is only 3KHZ.

One mod, however,  is VERY worthwhile.

Remove the 5U4 rectifier tube and replace it with a 5V4. This simple mod will give you a delay in the application of the B+, which will improve the life of the entire radio.

Now-I know some of you will know that the 5V4 does not have the current rating of the 5U4.

This is true, but in this application this does NOT matter, as the pass capability of the 5V4 exceeds the requirements of the radio.

Chuck

N1LNH