[ARC5] 5th Receiver Drift Test from KE6F Hammarlund HQ129X

[millerke6f at aol.com]

Hi to all


	Included in this posting are the results of the drift run I performed on my HQ129X receiver.  The unit has been in dry storage for about 10 years, but is in good mechanical condition and powered up without too many complaints.  The Ambient temperature during the test hovered at 62 degrees F.  Once again the Agilent E4400B signal generator was employed. Only 80, 40, and 20 meters were tested as the initial drift run on 80 meters suggested that the overall drift performance of the radio was not going to be stellar.   The unit was allowed to warm up for 30 minutes before the first drift run was made.


80 Meters


3:30 pm	3.700000 MHz (start of run)
3:45 pm	3.699330 MHz (670 Hz change)
4:00 pm	3.698944 MHz (386 Hz change)
4:15 pm	3.698200 MHz	(744 Hz change)


40 Meters


4:00 pm	7.200000 MHz (start of run)
4:30 pm	7.201001 MHz (1001 Hz change)
4:50 pm	7.201150 MHz (149 Hz change)
5:05 pm	7.202280 MHz (1130 Hz change)


20 Meters  (I ran the 20 meter test longer to see if prolonged heat soak would improve the radio's drift performance


5:10 pm	14.200000 MHz (start of run)
5:15 pm	14.200940 MHz (940 Hz change)
5:30 pm	14.201700 MHz (760 Hz change)
5:45 pm	14.202700 MHz (1000 Hz change)
6:30 pm	14.203590 MHz (890 Hz change)


I did a bit of on-the-air listening to the unit on 75 meter SSB to see how well it worked as a general purpose receiver on the low Hf bands. I had to re-tune every 20 minutes or so to keep the voice sounding natural on an evening net on 3.952 KHz.  The overall performance was adequate for general listening on CW and AM but a challenge on SSB. The Crystal filter scheme worked nicely and the tuning was smooth.


Tomorrow I hope to get the 51J4 or the Hallicrafters SX101A on the bench for the next run


thank you for the read and the feedback


73  Bob, KE6F