I have had this old late 1980's cellular preamp around for many years and decided to bench it and see if I could retweek it from the mid 800mhz range to 902mhz and had success. Removing the cover exposes the guts and there is a small open type cavity with two coil adjustments to the left. After using the shop R2670 tracking generator on 902.9625 I was able to move both coils down in there range and get about 10 times out from what I put into the input. The external gain pot also has to be set for maximum. After tweeking it I tested it on a GE TMX9315 (with the 915mhz filters) which is pretty deaf at 902 (takes about .5uV just to open the squelch) and it only took .15uV into the preamp to get a full quiting signal into the old GE. This could of course be usefull in building a repeater which is why I thought I would share with you folks. It is pretty broad banded so you would have to insert a narrow rx filter between the preamp and receiver. I have seen these sold on ebay and on some other commercial equipment supplier web sites but they always seem to be cheaper on ebay. I have several pics I would like to post here but not too sure how to do that. Perhaps someone else could do that for me if I could send them. Thanks...Dan n2aym
PS - I think this preamp is actually made by celwave cause it very closely resembles the celwave line of preamps but could not find any celwave part numbers on it when I had it appart.
Motorola PF849M Cellular Preamp
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Motorola PF849M Cellular Preamp
Last edited by fineshot1 on Wed Jan 25, 2006 2:48 am, edited 1 time in total.
fineshot1
NJ USA
NJ USA