trunking system found on side of road!

[transistor747]

I was just given a 900MHz Motorola trunking system that has been removed from service. 5 channels of MSF5000 and a startsite controller. I noticed one channel was 939.xxx transmit.
Anything decent for ham use here?
Otherwise I'm probably going to part it out for PA's, racks, combiner, UPS, etc.
Sam

[xmo]

The MSF5000's go to the 900 ham band with re-programming and standard alignment. They make excellent ham repeaters.

Obviously, you also re-program them from trunking operation to conventional.

[kcbooboo]

The MSF5000 should be usable on the ham band, as it would normally receive 896-902 and transmit 935-941. As you know, they're terribly heavy, so shipping could be expensive.

I can't tell from your first post if there are 5 MSF5000s or just one that has 5 channels in it.

If the price is right, I'd certainly be interested in an MSF5000 (CXB) on 900 MHz !

Bob M.

[transistor747]

There are five MSF5000 repeaters.
Off hand I don't know the model #, but I'll check.
They are probably at least 75 watts, it's that size cabinet.
Yep, heavy for sure.
Sam

[xmo]

One of my 900 repeaters is an MSF5000 that I bought from an ebay auction. Before bidding, I contacted the seller who agreed to ship it in pieces.

By removing the power supply and PA and boxing each of those 40+ pound items, you can ship via UPS.

It seems to me it cost about $100 total to ship the pieces.

[Jonathan KC8RYW]

Heh, a 33 cm Motorola trunking system.

That'd be fun.

[transistor747]

The model # of the MSF5k repeaters appears to be G85GFB5200AT.
I forgot to bring my old man reading glasses.
The controllers do have the 3 led window on the right side.

What is the typical split on a ham repeater at 900?

There is a 5 channel combiner system.. shame to waste. Also the bottom end of a Decibel Products preamp.
Did I say it had a Startsite controller?


I have offered one repeater as a gift to the local ham club, so one may be spoken for.

[batdude]

the GFB is (i think) the MSF "LIMITED" part number.

these are computer programmed- and were only LIMITED in the fact that the factory did not perform any customization of the station prior to shipment - it was a buy it as we build it type thing - no special mods.

the startsite controller alone is worth more than the stations - some of the parts in the startsite are NLA - and those can bring decent coin as people snap them up soley for parts.


doug

[Jonathan KC8RYW]

What is the typical split on a ham repeater at 900?

25 MHz.

Repeater inputs on 902.500 - 902.9875

Repeater outputs on 927.500 - 927.9875

The Motorola GTX (popular no-mods portable and mobile) starts to get deaf below 927.500.

[xmo]

1) GFB is the PC programmable 900 MHz series of MSF5000 stations known as "Analog Plus" - basically the same as the VHF/UHF/800 "Digital Capable" stations but without the Securenet option.

2) What sense is there in recommending the use of a Maxtrac mobile as a repeater receiver when the MSF has an infrastructure grade receiver built in that will tune right to the ham band????

[Jonathan KC8RYW]

2) What sense is there in recommending the use of a Maxtrac mobile as a repeater receiver when the MSF has an infrastructure grade receiver built in that will tune right to the ham band????

Oops. I edited my last post to correct this error on my part.

[xmo]

You were probably thinking PURC5000. There are a lot of those stations around - and since they don't have a receiver - the Maxtrac is a great way to turn one of them into a repeater.

Also, the MSF has a pretty versatile controller with programmable CWID - to get on the air you can do it all in the MSF.

If the use of an external controller is desired, the CXB/RLB/GFB PC programmable stations are very easy to interface. Unless the wireline interface was omitted or removed, there is a programmable input and output that can be configured in the RSS to be PTT and receiver activity indicate respectively, plus there is 600 ohm receive and transmit audio all available on the station option connectors.

Just program the station to not repeat internally, hook those connections to your Arcom, Link, Cat, Scom or other controller, set your levels & you're on the air.

[transistor747]

Would a Smartzone repeater normally have a wireline interface?
I would not have thought so, but still.
It was sold by a /\/\ salesman with a quota.
Sam

[xmo]

The wireline and trunk interface capabilities require the same boards so your stations surely have them.

[TTRC = Trunked Tone Remote Control - 2 board set - audio & control]

[n1pfc]

What is the typical split on a ham repeater at 900?

25 MHz.

Repeater inputs on 902.500 - 902.9875

Repeater outputs on 927.500 - 927.9875

The Motorola GTX (popular no-mods portable and mobile) starts to get deaf below 927.500.

There's a few 12MHz split ones around too. But good luck getting anything to work with that other than a modified maxtrac. That is the only M radio I know of that can deal with 12MHz splits and still be sensitive enough to function as a real radio.

I'm already using a Nucleus for my TX and a maxtrac for my RX on my 900MHz repeater. (927.7375)

Last I checked was putting 100+ watts out of the duplexer to a 7dBd antenna.

Nucleus feeds 180W to a 3 can paging transmitter filter then the duplexer.

The maxtrac gets RF from the duplexer which then goes through 2 more cans of filtering (I've got 2 more if I need em)

Last checked isolation was 130dB+ between TX and RX. I dont think I need the other 2 filtering cans on the RX.


Kurt

[kcbooboo]

As posted above:

Repeater splits: 25 MHz.
Repeater inputs on 902.500 - 902.9875.
Repeater outputs on 927.500 - 927.9875.
The Motorola GTX (popular no-mods portable and mobile) starts to get deaf below 927.500.

The above frequency limits may vary by your geographic area. The new upcoming "standard" is for inputs to go from 902.4 thru 902.9875, and for outputs to go from 927.4 to 927.9875. Still 25 MHz separation. The 12 MHz repeaters, if any, are allowed to continue.

The 900 GTX radios, like MaxTracs, have front end filters centered at 938 MHz and they're about +/- 15 MHz wide. The receivers will have usable sensitivity down to about 920 MHz (perhaps losing 1-2dB down there) but may not hear a thing down at 918 because the VCO won't lock up that low. See the data in the GTX Info page in the Motorola section on repeater-builder.com.

By the way, you don't need nearly that much isolation (130dB) to get things to work well. My Nucleus transmitter is feeding 150 watts into a four-cavity Bp/Br, Bp duplexer which gives me about 80dB isolation on each side, and even with a preamp I get absolutely no desense. Remember that we're dealing with 25 MHz splits here, and that gives an awful lot of isolation even before the duplexer does its job.

Bob M.

[n1pfc]

Oh I know I dont need that much isolation, but I needed more than my 2 can duplexer was going to give me according to spec at 140W into it. So I put the additional filtering on it just in case.

Kurt

[MSS-Dave]

Sam...

Check your PM please...

Dave

[transistor747]

Good morning folks,
I've decided to peddle these five MSF5000 900 MHz repeaters. I'd love to see them go into ham use, and would prefer to offer them to this group.
So... I'm thinking $500.00 each is fair? If not, let's discuss it.
I'd be willing to discount for more than one unit.
They would ship from 70663, or will be certainly available for pick up locally.
This was a complete system, so there is also a controller, combiner, UPS, etc.
Hopefully this post won't offend a moderator.
Sam

Oh, I should add that I'm more than willing to swap... whatcha got?

[n9wys]

I realize I'm getting in WAY after this thread was active, but are any of these MSF rigs still available??

I'd be interested in one for ham use here in IL. And $500 is not out of line for me.

[transistor747]

All of the equipment has been sold. The repeaters went into amateur service in the Dallas area I believe.

Sam

WA5VDM