Batboard

Guys,

This is my first post here. Most likely won't be my last one either.

So here goes.

I have a Motorola R-2001 that has seen better days. It works, more or less. Everything seems to function. Scope, counter, dvm, monitor, and so on.

What doesn't work work is the attenuator.

No, that's not right.

The attenuator does work. But on the CRT, it tells me to reduce level (with the Motorola R-2001 in generate mode)

The small variable knob next to the step atten doesn't seem to do anything.

when I turned the small variable output knob, the display flickers and you can see mV and dbm for a split second or two, then the CRT says to reduce level.

I connected the output of 2001 into my scope and when I adjust the step atten, I can in fact, see the level drop

however, adjusting the small knob next to the step atten, it does nothing to the output.

Any ideas? Anyone?

thanks...

Mike

Let me ask a question here. When you see this message, are you trying to measure the TX power of a transmitter? If so, the message is telling you to add attenuation to reduce the signal going into the service monitor. Plus you had better not be using the BNC RX input connector. You will blow the input to the service monitor. You should be using the type N connector to measure a transmitter.

Jim

I'll second Jim202's statement. Also have you pulled and reseated all of the cards in the unit. My 2001C had various little issues that a tap would fix and pulling the cards, cleaning the connectors with a "Pink Pearl" eraser and plugging back in cured that. Been stable ever since.

Mitch
N4MF

thanks, Mitch and Jim,

No, not connected to a transmitter. That would be bad mojo!

I'm in generate mode.

The sweep generator won't work either as it says (on the CRT) to reduce level.

Oh yeah, pulled all the cards, good 'ol pencil eraser. Unplugged and replugged the various ribbon connectors, too.

No joy.

I don't see where there has been fingers inside this unit. Nothing is mangled or manhandled that I can see.

When I monitor the output of the generator on my scope, I can see the attenuator cut the output from the main selector, but nothing from the small variable control. So, question.

Shouldn't I be able to see the level (on my scope) drop as I lower the level on the fine variable control?

I don't see that happen.

Mike

Your problem is in the wideband amplifier section of the RF I/O module.

Is that the A11 module?

The long aluminum box that the RF N connector is installed to?

Oh happy day...

mike

Here is the scan of the service manual copy I made. about 42meg
http://keekles.org/~w9cr/Motorola-R2001 ... Manual.pdf

The operators manual
http://keekles.org/~w9cr/Motorola-R2001 ... Manual.pdf

Good luck!

Thanks.... I suspect repairing this unit is beyond my skill set.

What I really need now is a phone number call and see about repair

mike