Motorola R-2200A Service Monitor Problems

[KE9GK]

Hello All!

I have a R-2200a service monitor with a few problems. I picked this thing up for a couple bucks from a guy that said it was working correctly (yea there is egg on my face) expecting to use it as my portable test unit (my HP8924 is just way too heavy to lug around). I notice that deviation alarm, power meter reading, and actually the deviation reading (period) doesn't work when I am using the "N" connector. The signal generator works just fine through the audio output connector...but when it comes to the RF port....it is severely attenuated. The HI GEN also works with about the same degraded preformance...I thought it may be the fuse..but the thing hears NOAA just fine from a rubber duck on the port. I am also noticing that when using the regular signal gen function...I cant turn down the audible 1000 hz tone...in fact its so loud its irritating after about 30 seconds...I also notice that I have OVR and PWR flashing together on both LCD screens...and they are blank except for the freq displayed in the LH one. Is this thing junk...or does anyone think they could assist me in getting the unit operational again. I DONT have the service manual...and wouldn't mind paying someone to calibrate it...but I am thinking hardware failure and not just alignment concerns???

Thanks All

[desperado]

Measure the resistance across the N connector, if it's not 50 ohms then there is an issue with the connection between the connector and the internal load.

The BNC connectors for the ANT and the RF out are fused. Consult the owners manual for the part number of the fuse. It's a small leaded fuse that looks like a 1/4 watt resistor with no stripes.

Short of that, the attenuator network may have a problem.
It can be a bit difficult to fix, due to the tight tolerance parts inside and getting it back to a calibrated accuracy may be impossible.
But, I am not certain that unit can be calibration stamped any more due to the age of the unit. It may be in the 'best effort' status for being cal'ed.

Since you have the 8924, you have a source for doing a calibration yourself. It can act as a reference to work on the 2200 and bring it back to life.

Keep us informed of your progress.