RadioBanter - HELP!! Motorola R-2001D Service Monitor

Larry McGee wrote:
Hello and thanks for the read.. I have 2 R-2001 service monitors that have
low Generator Mode output.

The specs are that the output should be low of minus 127 dBm to a high of
plus 13 dBm using the step switch and variable.

Both of these units output a low of minus 147 dBm to a high of minus 17 dBm
using the step switch and variable.

While in the Generate Mode, the next line below the actual Volt/dBm reading
line reads:

DIST/SINAD INPUT Too low

On the older R-2001B monitor in Generate Mode, that line is SINAD DB with a
bar (graph?) below it.

Any & all thoughts are appreciated. Is it pilot error on my part? Settingd
on thr Front Panel? Internal setting problem?? Or ????

Thanks for your help. Larry

Larry; It has been a while since I have used one of these models.

1) There is a fuse under the BNC connector for the GEN out which
sometimes gets blown. Unscrew the BNC and you will find it, it looks
like a resistor nut is a very small value fuse. When it blows, your RF
output from the GEN out is greatly reduced.

2) You can push or pull the RF out vernier to select different functions
(I forget which) Perhaps high RF level or GEN out mode (BNC connector)
vs Duplex (N connector). I don't think you get full generator output
from the duplex (N Connector) port because it runs through a high power
attenuator pad. But it should be calibrated properly on the low end of
the range.

3) How are you measuring the RF levels? Describe how you are set up.

4) The SINAD meter won't read anything unless you generate an FM carrier
modulated with a 1000 Hz tone at +/- 3.0 KHz deviation (60% modulation)
into an suitable 25 khz bandwidth FM receiver and connect its audio
output to the scope/SINAD input. It is an audio distortion analyzer with
a SINAD calibration mode. You can spoof it by looping a tone out from
the audio generator to the SINAD input, but the SINAD will be so good,
the bar won't move much from the left unless you switch to AC DVM mode.

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Use only Genuine Interocitor Parts" Tom Servo ;-P