[Premium-Rx] receivers with 20Mhz IF?

[Michael O'Beirne]

Good morning gents,

Regarding Eugene Hertz' posting on the 25th May, I once tried connecting my elderly Marconi TF2370 spectrum analyser to the IF output of an RA1772 (IF output on 1.4MHz) as a spectrum monitor.  Unfortunately I could not find the right combination of sweep time, sweep width and filter bandwidth to give a fast on-screen display because these controls are cross-linked for operator ease and you don't have the switching freedom as with the HP 141.  I found that the specialist made-for-the-job panoramic adaptors are far better.  For VHF with an IF input of 21.4MHz, the best I know of (so far) is the Racal MA2313E with a display screen the shape and almost the size of a traditional letterbox.

Has anyone tried to add a panoramic output on a RA1792 (or similar) using an FET buffer amp feeding from between the 1st mixer output and the roofing xtal filter?  Would the added load and capacitance distort the filter response or degrade the mixer's performance?

For those interested, summer has finally arrived in England, but so has the release of pollen spores.

73s to all
Michael O'Beirne
G8MOB
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