Front end RX sensitivity MTS2000 vs HT1250??

[g8tzl2004]

I wonder if anybody has compared the front end receive sensitivity of the MTS2000 compared to the HT1250/HT1550/GP340 etc.

Which is best using an identical external antenna rather than the stock whip?

At least the MTS2000 uses a "sensible" reverse SMA rather than the "nasty" HT1250 arrangement which requires a "special Motorola" BNC adapter!!!! - a backwards step if you ask me!! - although I also needed a BNC adapter for the MTS2000 SMA!!

[escomm]

Yeah, you might not realize this but the reverse SMA is singular to Motorola and I really don't see how it's different from the "special" connector on the HT1250... Motorola has been using that style connector for 25+ years...

As for sensitivity... somebody find me a family of radios that Motorola built that is/was better than the JEDI... simply put the JEDI portables are the best Motorola has ever made... IMHO

[g8tzl2004]

Years ago I was sent the wrong SMA/BNC adapter - a reverse rather than the normal. I thought about sending it back but thought that it might come in!! Not only is it useful for Motorola Jedi's but also some Yaesu/Vertex ham stuff and other European LMR radios!!

Motorola also has the "mini UHF" on MCS2000 radios - requiring yet another adapter. Thankfully CDM's are now BNC!!!

[escomm]

Huh? CDMs utilize a Mini UHF connector, just like every Motorola mobile radio on the market right now.

[g8tzl2004]

"European" CDM's ie. GM340/GM360/GM380 use BNC's!!!

Interestingly, I saw some CM140's the other day (not sure of American designation) and they had "homebrew" BNC's fitted - looked a right mess!!! So maybe they were originally mini-UHF connectors??

[AEC]

I don't think I've ever seen a Circcle-M radio(mobile) with anything but a mini-UHF connector.

The entire mobile product line has always been fitted with the mini-UHF.

Maxtrac, SM series, M1225, Spectra, MCS, GTX, XTL.....Use this cheap connector.

While its usable frequency range is actually good through1 gHz, it doesn't have the mechanical ruggedness as the bodies are cast pot metal(usually) and are very prone to corrosion and electrolysis action(eaten away easily).

It's all about cost...nothing more.

A mini-UHF crimp connector is far less costly to produce than a BNC, SMA or even a PL-259.

While the Jedi has a darn good receiver, the Saber was the top of the line during its heyday, and could stand up against anything made back then.

Solid state device tecchnology kept moving forward, and the Saber was a 1970's vintage production when it began, so there is no comparison to make as the
ability to fabricate Gallium Arsenide small signal devices were far more difficult to produce, unlike today.

[escomm]

and the Saber was a 1970's vintage production when it began

Huh? Late 1980s there..... 1970s portable radios were controlled by rocks.... I don't think the MX300S came out until the very early 80s... hell I don't even think the Syntor came out til the 80s either...

[AEC]

My error Jeff...

I believe they came out in the mid '80s, but they did predate the Jedi by several years.

Somewhere in my archive, I have a coporate paper Circle-M printed comparing the M-PD by GE against the Saber.

Pros and cons of each, of course, the Saber took top honors, and you can see why too.

I never liked the M-PD for many reasons, with the biggest being overly bulky and with painted plastic and chrome that wore off.

Tuning these critters wasn't fun either, and the adaptor cables required were a pain to work with( I still have my issued cables).

The KPC was built shoddily as well, with the keypad held in with a silicone adhesive, and the radio rattled for some reason.

But I still love the TK-250/350G series portables of the 90's.

I wish I still had mine.

As for the Saber, for their age, they are still top performers, and the design will be a classic long after they have finally been put out to pasture.

I am not a dealer and no longer have ready access to company information or literature that is sent to dealers, so I have to rely solely on what I have, or what I remember.

This is why I obtain line cards when and where I can.

I deal with service only, at least I can do warranty returns and out of warranty service as well.

[tvsjr]

Most of the Euro Moto radios use BNCs. I think it has something to do with getting the radios CE certified.

For my part, they can bring those BNCs over to this side of the pond and get rid of the infernal mini-UHF once and for all.

[AEC]

Most of the Euro Moto radios use BNCs. I think it has something to do with getting the radios CE certified.

For my part, they can bring those BNCs over to this side of the pond and get rid of the infernal mini-UHF once and for all.

I couldn't agree with you more!

I can't stand the cheap junk Circle-M uses.

The tolerances between M & F connectors is horrendous, with crossthreading issues, center pins snapping, and simply crimping the damn things is crazy!

Whatever happened to a real, SOLDERED connection?

[tvsjr]

Whatever happened to a real, SOLDERED connection?

Something about maintaining a constant impedance.

Crimp is just fine when installed with proper tools, but Mini-Us suck due to vibration causing the connectors to loosen and center pins failing. BNC > MiniU.

[Jay]

I have had the occasion to replace a faulty mini-UHF on a CDM mobile once, and ordered the wrong part number from the service manual. When the parts arrived, I ended up with a BNC. So for what it is worth, they are available for that series if you want to go through the trouble of replacing one.

Jay

[RADIOMAN2002]

MX-S radio was first introduced in VHF in 1978. I have a few of them.

[WB6DGN]

BNC > MiniU.

Well, they say there's always got to be "one", so I'll be IT for this thread. Except for test equipment, I can't honestly say that I like the BNC any better than the miniU. Had my fill of those, and then some, during my avionics days. Now, the TNC is a horse of a different color. In my opinion it is second only to the good ole "N" connector. I don't understand why it is not more widely used. As for crimp connectors, I'm a believer! As long as they're assembled correctly, with good quality tools, they beat a soldered connector hands down (follows the requisite disclaimer) in my opinion. Just food for thought.
Tom DGN

[motorola_otaku]

BNCs, Mini-UHFs, and TNCs all have their place. I'm just glad they got away completely from using PL/SO-239 connectors. (*cough*Kenwood*cough*Vertex*cough*)

As for sensitivity, I hate the Waris line and have next to no experience with them but the Jedi (MTS) line beats the XTS/Astro line in general, non-scientific terms, and the good ol' analog Saber has a slight edge over the Jedi line in sensitivity and a big edge in selectivity.

[Will]

In our tests for a railroad customer who had poor reception with their HT750's vs the HT1000, MT2000, Jedi radios. Bench testing the Jedi was much better. With standard antennas the HT1000 beat the HT750 with a lot to spare.
Motorola even "upgraded the HT750's and the RR still had poor reception. (2001)

The Jedi receiver frontend filter is trac tuned allowing much better sensitivity and better intermod rejection VS the broad fe HT750.

[g8tzl2004]

Will - does that mean that a "pre-2001" HT750/1250/1550 has poorer RX sensitivity that a "post-2001" identical radio ??

If so, then I guess its important to always check the manufacture date!!!

[jims123]

Here is part number you need to perform check out in HT1250/750 0985613Z01 check with motorola online for cost.

[g8tzl2004]

I've done some brief RX sensitivity tests with a VHF GP340 (HT750) and a UHF GP380 (HT1250).

The VHF GP340 (HT750) was manufactured in April 2004 and the RX performance is very good. It equals some of my best stuff!!

The UHF GP380 (HT1250) was manufactured in Sept 2005 and is an "EX" intrinsically safe version. Its RX performance is OK - maybe 1-2dB down on some of my best stuff .

Both radios have excellent carrier SQL circuits which can be set to open on the weakest of signals.

I have yet to do much testing with my UHF MTS2000 Flashport - its actually over 1KHz off frequency so direct comparison is not perfect and the SQL threshold is much too high for weak signal comparisons. It will be interesting to see how I get on with lowering the carrier SQL level on the MTS2000. On other portable Jedi's, I've had real problems sorting out the SQL threshold level for weak signal working. There is also a common mixer/IF problem with many Jedi's which cause SQL issues on weak signals. My MCS2000 UHF mobile has excellent RX performance and an excellent carrier SQL circuit!!