Batboard

Hi, Happy new year. I have a tle2512a p.a. unit. I believe that it is part of the msf5000 system and is uhf and 13.8 volt. After extensive research on the net over several weeks I found this site! I have seen a similar unit on repeaterbuilder physically the same but with different board numbers. Can anyone provide definite info. or is mine the same as the one on repbuild? Devices are M1107 and 11L60. 73 de Max.

TLE2512A = C74CXB series MSF5000 110 Watt PA, 435-475 MHz

Contains:
1) TLE5422C Pre-Driver Hybrid Module
1) TLE5432A Splitter Power Amplifier Hybrid
1) TLE5828A Power Combiner Hybrid
4) TLE5830C Laser Trimmed PA Module Hybrid
1) TRN5204A PA Distribution Board
1) TRN5205A Feedthru Plate
2) TRN5207A Balancing Resistor
1) TTE6212A Small Circulator

Tnx XMO for the prompt reply. Much appreciated. I will now go and play with it! 73 Max.

Power input to drive this amplifier is nominally 3 - 5 Watts.

When the PA isinstalled in the MSF station, its RF power output is determined by a closed loop control system. The IPA [Intermediate Power Amplifier] stage that supplies the drive to the PA has variable output power. The power control loop circuitry is on the station's Uniboard.

Tnx for the info. I assume that is what the grey cable with the (Molex?) connector is for. How can this be defeated?

Hi Max,

You can operate the RF Power Amplifier without the closed loop although I would recommend providing less than the 3.5W RF Drive to the UHF Amplifier. This way you'll have a better chance not to over drive the P.A. transistorized Finals. That power amplifier is rated at 110 Watts Output but if the power amp has a built in circulator (rectangular metal box), you should have 100 Watts at RF Output connector.

Generaly speaking when it came to repairs on the RF transistors, /\/\ personnel were instructed to replace the entire individual nodules $$$$$$. The /\/\1107 and the 11L60 are /\/\ Global Part numbers.

M1107 => 4884411L07 => SRF2384 NPN Silicon

11L60 => 4884411L60 => RF499 NPN Silicon

Dan

Hi Dan,

thanks very much for the info. It is much appreciated. A local G3 friend used to work for Motorola (ex Storno) and told me on many ocassions that they rarely worked to component level on repairs! All the best, have a good weekend. Max.

Re TLE2512A amp. I have tried it and it works but I am getting no power out below 450MHz. 100 watts out for 2 watts of drive on 460MHz! Are these things tweakable? What is the purpose of the stripline stubs on the bases and collectors? Is this the laser trimming? Do these stubs tune the modules? There does not appear to be any output filtering, although I
have not tried removing any boards. 73 all Max.

The amp should function from 435 to 475 or so.

This amp is part of a complex, high-gain power control system that regulates the output power by varying the drive power. The driver is capable of up to about 9 watts. The power control circuit has a lot of gain, and responds quickly and with whatever force is necessary to keep the output signal (sampled voltage from the output of the PA) constant. The power amp can easily put out in excess of 150 watts.

These units typically have a single or triple circulator built in, and they're always followed by some kind of bandpass or low pass filter. Thermistors on the PA and in the circulator are also part of the power control logic, and they would lower the drive power if the unit gets too hot.

The laser-trimmed capacitors on the modules are done at the factory. There is no field tuning required or possible. The amp is broadband. 2 watts of power may just be a bit too low; try increasing your drive power a bit and see if that helps. Typically, 3-4 watts of input power are provided at 445 MHz, but I don't know how much or little is needed at other frequencies. Only a very slight change in drive power is required to see a big change in PA output power.

Bob M.

Are these easy to replace the finals in? I have one that came out of a 472 MHz LTR system and I put it into service on the UHF ham band. It was running a good 150 watts before the duplexer with 95 watts after the duplexer. Within two weeks the unit must have lost it's last stage driver because now it's running at 80 before the duplexer. I have another system with the same exact PA (TLE2512A) that's been running over 2 years at 460 MHz with no problem at 150 before the duplexer. Why did this other one die? Not enough cooling?

Also, can anyone with a MSF5000 manual tell me what a TTE1462 comes back to? My 5000 manual is on a leave of absence.

The TTE1462 is referenced to a 110w PA Deck: 435-475MHz
Doug

So then what is the difference in this and the TLE2512A? Maybe then it will work?

I really don't believe there is much of a difference. Perhaps someone more in the know can help. The main thing I've seen between the two is the way they are tuned for the specific range. If memory serves me correctly the 2512 uses laser cut tunning strips and the 1462 uses a jumper or a sort of solder bridge on the modules.
Doug