What technical similarity do HRO receivers and Elecraft receivers share that is unique? - Answer

[Elecraft mailing list]

Hi Don and others-   Ok.Here is my answer-  I don't think I am far off by saying that the unique similarity it is in using switched components to effect frequency coverage of the same tuning coil. In the HRO they had clips you could change over to go to "bandspread" mode on each coil assembly, Elecraft uses relays (switches) to change capacitor values in their bandpass filters so that the same assembly can cover two ranges. Essentially the same thing. I don't think any other companies have used this technique as extensively as National and Elecraft.
    Your opinion may vary.........    Doug
 Dr.Doug Millar EdD.
K6JEY
[hidden email]
562 810 3989  cell/text

 
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[Charlie T, K3ICH]

The Hallicrafters SX-73 used three selectable fixed very low value resistors to alter the Q and hence, the passband of three IF stages.

Does this qualify?

73, Charlie k3ICH


If you happen to own one, I'd strongly suggest checking these resistors.  I have two radios in for restoration, where the resistors were off by as much as a factor of 3 which completely screwed up the alignment.

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of Doug Millar via Elecraft
Sent: Sunday, September 03, 2017 8:46 PM
To: Elecraft Reflector <[hidden email]>
Subject: [Elecraft] What technical similarity do HRO receivers and Elecraft receivers share that is unique? - Answer

Hi Don and others-   Ok.Here is my answer-  I don't think I am far off by saying that the unique similarity it is in using switched components to effect frequency coverage of the same tuning coil. In the HRO they had clips you could change over to go to "bandspread" mode on each coil assembly, Elecraft uses relays (switches) to change capacitor values in their bandpass filters so that the same assembly can cover two ranges. Essentially the same thing. I don't think any other companies have used this technique as extensively as National and Elecraft.
    Your opinion may vary.........    Doug
 Dr.Doug Millar EdD.
K6JEY
[hidden email]
562 810 3989  cell/text

 
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