Motorola R2670A Tracking Generator

This forum exists for the purposes for discussing service monitors (This includes but is not limited to Motorola, HP, Aeroflex, GD, etc). Additional topics allowed include test procedures, interpretation of test results, where to find information about specific tests, antenna VSWR, return loss testing, duplexer and filter alignment, etc.

Moderator: Queue Moderator

Post Reply
User avatar
fineshot1
Posts: 1125
Joined: Wed Oct 12, 2005 5:13 am

Motorola R2670A Tracking Generator

Post by fineshot1 »

Has anyone had a problem like this? I have never encountered it with the monitor I have.
I used the TG on a new filter and the filter output is 60dbm down from the filter input
from the TG. The filter manufacture says the filter is good no problem. I made sure all
my RG224 coax cords that I have used a lot lately are good with other known good filters.
This particular filter has a pass and reject. The reject looks just fine to me but the pass
output is about 60dbm down from the input. The manufacture used an analyzer and I am
sure it is probably better than my service monitor. I am stumped!
fineshot1
NJ USA
jry
Posts: 481
Joined: Fri Feb 06, 2004 3:14 pm

Re: Motorola R2670A Tracking Generator

Post by jry »

not sure how you have your unit configured but I would start with jumpering the selected output to the antenna and verify that you get roughly the same level at the center freq.

The R2600 TG is not all that flat at wide dispersions and you tend to get a sawtooth when the SW stitches the screens together
User avatar
fineshot1
Posts: 1125
Joined: Wed Oct 12, 2005 5:13 am

Re: Motorola R2670A Tracking Generator

Post by fineshot1 »

jry wrote:not sure how you have your unit configured but I would start with jumpering the selected output to the antenna and verify that you get roughly the same level at the center freq.

The R2600 TG is not all that flat at wide dispersions and you tend to get a sawtooth when the SW stitches the screens together
No antenna was in the configuration. Input side of the filter was connected to the 2670A generator out and the other side of the filter was terminated to the antenna connector of the 2670A which is the way the tracking generator is used.
fineshot1
NJ USA
jry
Posts: 481
Joined: Fri Feb 06, 2004 3:14 pm

Re: Motorola R2670A Tracking Generator

Post by jry »

meant the antenna port on the R26XX.

Which output port did you use ? I think you may want the Duplex since that is 0dbm to -80dbm.

If that is off check the fuses on the antenna and duplex ports
User avatar
fineshot1
Posts: 1125
Joined: Wed Oct 12, 2005 5:13 am

Re: Motorola R2670A Tracking Generator

Post by fineshot1 »

jry wrote:meant the antenna port on the R26XX.

Which output port did you use ? I think you may want the Duplex since that is 0dbm to -80dbm.

If that is off check the fuses on the antenna and duplex ports
You are clearly not familiar with the 2670A. Duplex ???

This is NOT a fuse issue as all of the ports on this 2670A work flawlessly - i can with the
antenna connector receive the local NOAA broadcast. I tune cans of all types with this 2760A
all the time with no issues hence my being stumped with this one filter.
fineshot1
NJ USA
jry
Posts: 481
Joined: Fri Feb 06, 2004 3:14 pm

Re: Motorola R2670A Tracking Generator

Post by jry »

sorry ..different monitors different nomenclature for essentially the same thing. ( AUX, GEN , Duplex etc ... )

That would be the GEN port on the R26XX.

If the output level is close to the GEN setting at the center frequency using the correct adapter instead of the filter than maybe they tuned it to the wrong frequency and are checking it based on some bad info on the order. Using an adapter instead of the actual filter verifies your cables and provides their insertion loss.

Does it show a low insertion loss at any point on a wide sweep ? The R26XX SA levels tend to fall of on wider dispersions at the high end of the sweep.

More familiar than I would like some days with the series.
User avatar
fineshot1
Posts: 1125
Joined: Wed Oct 12, 2005 5:13 am

Re: Motorola R2670A Tracking Generator

Post by fineshot1 »

OK - problem solved. You were right jry. The Gen out conn had a blown fuse that i replaced.
Turns out that unknown to me one of my coworkers used the monitor before me and I assumed
he knew what he was doing. But as always human error can creep its way into anything. From now
on I will always fully check out the monitors tracking gen before using it. This can be done easily
by replacing the filter with a barrel connector adapter and turning your gen out back into your ant
connector having zero attenuation except any attenuation you have selected in your menu.
fineshot1
NJ USA
Post Reply

Return to “Test Equipment & RF Equipment Alignment”