Batboard

I know this is going to sound like a total newbie question... but here we go anyway,

What models of Motorola radios come standard with pre-amps, or is it an option when the radio is ordered. I friend of mine just installed an XTL1500 replacing a GM300 and the receive end was absolutely stunning in terms of clarity and signal strength. I have a scanner using a tri-band scanner built antenna, properly grounded that almost didn't break squelch to the same transmission (it was simplex freq, the guy Tx was using a HT1250).

I know the scanners usually can't receive as well as a transceiver built for the band being used, but I need a new mobile, and if there was a pre-amp in the XTL1500, and it sounded that clear, I would like to make sure the mobile I am buying has one.

I believe that what you are comparing are two distinct generations of radio receivers, with the newer one having digital signal processing after going through what has to be a later generation front end. Comparing the costs of a GM300 vs. an XTL5000 also tells part of the story.

Preamps are usually used in situations where the signal strength is marginal. They add signal but they also add noise. There is no free lunch when using a preamp although they can be helpful.

A communications receiver is always going to beat the pants off a scanner. I'm told that some of the very new generation scanners are pretty sensitive, but if given a choice I'd always take a current-generation comm receiver as long as I didn't need multiband coverage.

The point of comparing the GM300 to the XTL1500 (not 5000) was the difference in models... I thought there may have been something to it because he didn't specify why it was chosen over anything else like a CM300 or CDM. If you want power most of the dealers around the area are pushing the PM1500 so it was an odd choice. I thought it may have been the pre-amp. But it wasn't necessarily the sensitivity but it was also the quality. I should add his set up is using a magnetic mount quarter wave (did I mention this is all on VHF)

I guess as I understand it using a band specific transceiver does a much better than a scanner of receiving the same traffic. I have been slow to get a mobile just because there isn't very many good places to mount one, and I never saw it because I always pushed the distance requirements with my HT, but it is starting to annoy me when I have to repeat myself so it is time to get something more than 5W

I may be wrong, but I think the last models with a preamp option were the Spectras.

Current Astro25 mobiles (like the XTL1500 in question) have a preamp built into the board - they are after all uni-board radios. However, it's only available to be used if the radio was ordered with the W12 Preamp flashcode option.

On all prior models (Astro Spectra/Spectra+, Spectra, X9000, etc), W12 was a physical hardware option, a different front-end board that you would have to install in order to get the functionality.

And a moment of silence, please, in memory of that slick little plug-in preamp that was used in the Mitrek radios. I'm still using them in base stations here, though in strong signal areas they're actually overkill.

akardam wrote:Current Astro25 mobiles (like the XTL1500 in question) have a preamp built into the board - they are after all uni-board radios. However, it's only available to be used if the radio was ordered with the W12 Preamp flashcode option.

So they've built it in but still found a way to charge for it... typical.
I had looked at the basic service manual and it only listed one spec for receive sensitivity, unlike the Spectra which had specs for with and without preamp.
They mention it in the detailed service manual, looks like a 10-11dB gain LNA which can be switched on from CPS if you purchase the option.

I'll have to ask for the flashcode then (I doubt he knows what it is, he just knows how to talk into the radios - and even that is a challenge ) His son does programming for guys who don't have the ability to and don't want to pay dealer prices so he could have recommended for him. Again judging by the fact he jumped to an XTL1500 as apposed to a PM1500 or even a CDM* or a Commercial Series unit means that he probably liked one feature he could only get on the Astro 25 mobiles.