110 watt Spectra or Maratrac..Which one handles heat better?

[adamhannah]

--Hi, all. I am thinking about getting a new Moto radio for 2 meter FM, and I was wondering which one of these radios stays cooler during transmission, the 110 watt Spectra or the 110 watt Maratrac? Looking at the heatsinks, I would say the Spectra looks as if it would do a better job of keeping its cool. All pluses and minuses of each radio would be helpful. Thanks for the help.

[kc7gr]

Actually, either one would handle heat pretty well. However, the Spectra has more features, including alphanumeric display on the control head (the Maratrac is numeric-only).

The Spectra can also handle more channels (128 vs. the Maratrac's 32), and it has the capability of doing zone operation (groups of channels under a common name) if the firmware is release 6.0 or later.

Note that all Spectras have a common point of failure, one that should be checked (and, if necessary, promptly addressed) from the moment you get your radio. Specifically, there are several aluminum electrolytic capacitors on the command and RF boards (and in the control head on A4, A5, and A7 models) which leak and can damage the boards.

In fact, the first thing you should do when you get a Spectra is change out the caps to Panasonic HD series or a similar high-spec (or mil spec, if you prefer) part. If you do not have the tools and/or skill to replace surface-mount devices, and clean circuit boards, either myself or Will (another Batboard member) can do it for you at our respective labor rates.

No matter which of the two you settle on, I would strongly recommend turning the output power down to about 75 watts. This will make practically no difference in signal quality at the receiving end (since it's less than a 3dB drop), and it will greatly extend the useful life of the (unobtainable) final PA transistors. It'll also cut down on current draw and heat generated.

Happy communicating.

[n7maq]

The problem with the Maratrac in the ham band is below 146.00 you loose all of the softpot controls (this also happens with the Maxtracs). You don't know what the power out will be, and the deviation will usually do funny things. From my experience with them is the power out will shoot way up, and you end up burning the PA. I have seen this power jump on about a half dozen or so, and a few PA's out of that batch go out. The Maratrac is basically a high power Maxtrac. They will do 99 channels with the A7 head, or 8/16 with the clamshell head.

The Spectra is the way to go. Even though the Spectra bandsplit also stops at 146.00, I have not seen the "runaway" power output on them. As Bruce pointed out, you have a display with alpha tags, and its a better radio. The prices have come WAY down on them, I saw Mike Maureen selling the HP A9's for under $100.00. As far as replacing the caps, a lot of us on here can do that for a very reasonable cost if needed.

There are also a lot of Astro Spectras that have come on the used market at very good prices. For an analog unit without the 2.5Khz board you can get one for about the same the cost as the older Spectras were just a year or two ago.

Jim

[kf4sqb]

Jim, I'm not saying that the problem you describe with the Maratrac in Ham bands doesn't exist, but my brother has one that he's been running on 2m for quite a while now, and has never had a problem with it. We've never had it on a meter, so we don't know what the power output is in the 2m band (or anywhere else, for that matter), but he has run it for thirty minutes or better (TX and RX, not steady TX) in extended conversations before, and it doesn't seem to have hurt it so far. I've recently acquired a Bird 43, so it probably will get checked and turned down to 75-80 watts now. He's been wanting to turn it down for a while anyway, but neither of us had a VHF wattmeter until now.

With that being said, I'll still recommend the Spectra, for the alpha-numeric display if for nothing else. It gets old in a hurry trying to remember which channel number is which repeater or simplex frequency.

[W8RW]

Allow me to throw the Syntor X or X9000 into the mix. Old? Yes. But I would take one of these over a Maratrac. They won't melt down at 110 watts. The high band models are readily available for cheap.

[n7maq]

Jim, I'm not saying that the problem you describe with the Maratrac in Ham bands doesn't exist, but my brother has one that he's been running on 2m for quite a while now, and has never had a problem with it. We've never had it on a meter, so we don't know what the power output is in the 2m band (or anywhere else, for that matter), but he has run it for thirty minutes or better (TX and RX, not steady TX) in extended conversations before, and it doesn't seem to have hurt it so far. I've recently acquired a Bird 43, so it probably will get checked and turned down to 75-80 watts now. He's been wanting to turn it down for a while anyway, but neither of us had a VHF wattmeter until now.

With that being said, I'll still recommend the Spectra, for the alpha-numeric display if for nothing else. It gets old in a hurry trying to remember which channel number is which repeater or simplex frequency.

Check the power out and below 146.00, and above 146.00. Above 146.00 it's is OK. How did you check the fwd/ref power when you installed it without a power meter?

Jim

[kf4sqb]

Check the power out and below 146.00, and above 146.00. Above 146.00 it's is OK. How did you check the fwd/ref power when you installed it without a power meter?

As I said, we intend to check it, now that I have a meter to check it with. For original install, the antenna was cut to length with the cutting chart from the antenna manufacturer, and called good. Sucks to not have the proper test equipment, but I'm slowly working on that. Just got the Bird, and plan to get a good service monitor in a few months.