Ranger RCI-2950, Руководство по обслуживанию

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A 5V dip relay was used and the coil powered from the anode of D107 to allow a parallel combination of 3300uF and
47/2W resistor to be switched into series with the two final output transistors in the AM mode only. This produced an AM
swing from 100mW to about 4.5W
COMPARED
There is a big difference between the RCI 2990/Galaxy Saturn Turbo and the Galaxy Saturn.
The Galaxy Saturn is a Galaxy DX-88 in a box with 2 meters and a power supply. The frequency stabily in the Galaxy
Saturn, as with most other Galaxies, isn't the best.
The Galaxy Saturn _Turbo_ and the RCI-2990 are the same radio, albeit the different name and the Galaxy Saturn Turbo
comes with CB band enabled.
I have a Turbo and my neighbor has a Saturn, and in my opinion the Turbo/2990 is much, much more radio.
The Galaxy DX-11B is much like the Turbo/2990, with more echo controls on the front.
The Galaxy DX-22B is also like the Turbo, with no linear after it (so maybe 30-40 watts or so out, versus 120+ out of the
Turbo).
AGAIN
I was looking at the am det mod upgrade for the 2950... The radio I am working on already has 1N60 diodes for
d35-d34 , is this a mod that was done at the factory?
The bullten should be rewrighten to say what #diodes are there now and what they should be replaced with.....
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 0.02 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
incress AGC cut back from sig on other ch and improve S/NR and sen on all bands....
With these mods, realginment and installing a cascade RF RX amp makes the RCI 2950 Rx decent........
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