Upgrading Am Detection - Ranger RCI-2950 Service Manual

UPGRADING AM DETECTION

Change D34 & D35 that are 1N60's by ECG583 or SK9975. This mod will enhance the radio
performance.
Some version already have 1N60 diodes for d35-d34. The problem that is manifesting itself as AM
distorion ( and TX bleed) is caused by the lack of bandwith control due to the fact of the cheap Xtal filter
they use...
I improved the Am on my set by simply puting in a 0.002 Mfd NPO cap at the AM det output diode to
ground...This narrows the bandwith improves the S/NR and cuts some of the high freq audio distortion
out and provides smoothing and harmonic reduction from the AM det....
I further improved both the AM an SSB RX (and TX Bleed) by changing the Xtal IF filter... This mod will
also increase AGC cut back from sig on other ch and improve S/NR and sen on all bands....
With these mods, realignment and installing a cascade RF RX amp makes the RCI 2950 Rx decent........
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