As you may have determined, I favor the Motorola products primarily as I worked for a Motorola Service Shop back in the early seventies. That serious Motorola interest never went away although I have owned and installed a Mastr Pro UHF mobile and later owned and installed a Mastr Pro UHF repeater.
In regards to the ER-41-C Receiver, I believe I still have some GE factory info specifically related. If I can locate, I will send you a copy. Infrequently, I keep locating the info - now I want to find a copy, I probably won't be able. The article re http://www.gemoto.com/FM.htm I found is mostly correct in my opinion. The differences would bring up a good discussion at a party some time. Regarding your duplexing of the Mastr Pro mobile, I never had a whine problem that I remember ... even when I had outboarded a 16 button Western Electric Touch-Tone key pad wiring it into the microphone circuit. My UHF Mastr Pro had four frequencies too. Later, I had to modify that a bit when I decided to add my 4 frequency duplexed U64MHT Motrac and use the same 16 button key-pad with it. That Motrac transmitter, properly tuned, gave 40 watts output over a 3 1/2 MHz spread. I am not certain, but I may still have a TPL around the garage some place. If I can locate, I will certainly think of you. I know I have already donated all of my GE Porta-mobiles to a place in California. Same place got the MT-16 GE Progress Line, a high band GE Exec base station, one of the GE Exec II base stations a year or so ago. Neil McKie Kevin Custer wrote: > > Neil McKie wrote: > > > I think the politics with that was after the bad name GE had > > made for themselves with the Transistorized Progress Line (TPL) > > the Mastr Pro showed the county shop guys all was not lost. I > > know, I was impressed. > > > > This subject is touched upon on this page: > http://www.gemoto.com/FM.htm > > Notwithstanding my (slight) favoritism toward the Motorola line, the > GE Mastr Progress Line Professional (Mastr Pro) Mobile was my very > first repeater project in the fall of 1978; I was 14 years old. > > The ER-41-C receiver works so well. This receiver, despite having a > sensitivity of about .5 uV (-113 dBm) when pulled into the ham band, > will out hear many others. Someone a while back bitched about how > difficult it is to change out the helical resonators in a Micor, they > obviously never did a Mastr Pro high band..... > > I never cared for the switching power supply design in the Pro's > mobile, and it was very hard to reduce/eliminate the whine from the > repeat audio when you duplexed one. I'd have to find my notes as to > what I did, but a significant improvement could be had. The mobile > power supply was never intended for the duty cycle of a repeater, and > I often wondered when it would burn up. The tube multiplier and > final made it an easy chore to get it to duplex, even with a modest > duplexer. If one was so inclined, they would rip out the switcher > and build a nice line powered supply. This made a nice sounding - > more reliable repeater, but eliminated the easy battery back-up. > > The Mastr Pro was a great improvement over the TPL, and was likely > GE's saving grace. > > Kevin Custer > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
