[Hammarlund] HQ-100C Alignment

Mon Oct 19 19:42:21 EDT 2009

Bill,

It sounds like you may have the oscillator tracking on the wrong side.  I don't have my HQ-100 manual at hand but I believe it uses high side tracking on all bands which means the oscillator should operate 455 Khz. above the marked dial frequency.

Set the oscillator trimmer to about its midpoint setting.  I am assuming you have another fairly accurate receiver to use as a test receiver.  To roughly dial in the alignment on this band, set your test receiver to 12.455 (bfo on) and run an antenna lead from this receiver close to the HQ-100.  Tune the HQ-100 (bandspread to set point) around 12.000 to make sure you can hear the signal in the test receiver.  At this point your HQ-100 oscillator alignment is probably way off so you may have to tune the HQ-100 well away from 12 Mhz. so that your test receiver "hears" the signal.  Once you locate the signal note which direction you are tuned from the proper 12 Mhz. setting.  Move the HQ-100 slightly from the current setting towards 12.0 and readjust the oscillator coil so that the signal reappears in your test receiver.  This indicates which direction you need to move the slug.  Now tune the HQ-100 to 12.0 and adjust the slug until the signal reappears in the test receiver.  Now tune the test receiver to 28.455 and set the HQ-100 to 28.0 and adjust the oscillator trimmer to make the signal appear in the test receiver.  At this point it is roughly adjusted and you can then go back to the standard adjustment procedure in the manual.  This is my preferred way of setting the HFO in vintage receivers because you don't accidentally end up with wrong side tracking.  I keep a Grundig YB-400 on the test bench and it is perfect for this setup.

For the stuck slug, my best success has been with sticking a metal allen wrench into the slug and using a solder gun (iron would also work) as a heat source on the Allen tool.  Be very gentle (and careful not to burn yourself).  

Good luck!

Rodger WQ9E

-----Original Message-----
From: hammarlund-bounces at mailman.qth.net on behalf of Bill Stewart
Sent: Mon 10/19/2009 6:29 PM
To: hammarlund at mailman.qth.net
Subject: [Hammarlund] HQ-100C Alignment

Good evening all, 

I am in the process of trying to align a HQ-100C. The IF alignment went ok and with minor adjustments, the IF is on 455kc. Now for the RF. I'm not too sure about this but this is how I interpret the manuals directions: controls set same as with the IF adjustment; the VTVM still hooked to grid of V7 (6AL5) to read a neg. DC voltage; sig. gen. connected to the antenna input. First adj. the HF osc. per Fig. 7, top & bottom slugs adj. for max. at freq. specified. Secondly, make the RF adj. per Fig. 7: top slug adj. for min. at 1.65mc, bottom slug, max. at 1.65mc. Next adj. top slug at 4mc, bottom slug at 10mc...both max. amplitude(?). I assume the 4mc is the one on the 1.6-4mc band and the 10 is the one on the 10-30mc band. Make antenna adj. per Fig. 7. Lastly, the trimmer adj., per Fig. 8, if required. 

Now comes a problem. On the 10-30mc band, the rcvr is dead from about 11.5mc down to 10mc...no sig. gen. heard in this area. Above 11.5 or so, I can hear the gen., and with the antenna connected, sigs. come thru quite well. Also on the 10-30 band, the dial calib. is way off...over a mc., ie: 12mc dial = 13.516 sig. gen.; 11.5mc dial = 12.968mc sig. gen. This goes on up to 30mc dial = 33.268mc sig. gen. 

On a whim, I tried to adj. out some of the dial calib. error with the 30mc HF Osc. cylindrical trimmer cap (Fig. 8). The trimmer screw was out about 3/8 inch or so, but with it now all the way in, the dial error decreased slightly and is per the above para. 

And another woe is that the 10mc RF coil slug (bottom) is stuck. Is there anything safe to spray in the can or is a heat gun about the only 'safe' method to loosen it. Sure hate to have to remove it.  

Excuse the lengthy and rambling presentation...hopefully, it is understandable. I have some other issues such as the BFO not working right and an addition of the XCU-455 xtal controlled BFO, but this is quite enough for now. Thanks for any help/suggestions. 

73 de Bill K4JYS 

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