I joined the cult (New XG-100M owner)

[merlin]

Thank you very much! I've learned bits and pieces of this information the hard way. I ended up with a -007 charger when what I needed was a -026. It's difficult to find just the sleeves to swap in in order to reuse the electronics. I have some NOS NiMh batteries that I'm conditioning right now but having a drop-in charger would make life easier. Even though the 100P wouldn't drop in without mods to the sleeve I can still put in just the battery.

Swapping pockets, just be aware unity has 5 pins, others are 4. the base chargers in TriChem are all the same.

 

[splinter34]

Unity has 4 pins on the charging side of the radio, not 5. They use the same battery of a P7200.

 

[merlin]

Unity has 4 pins on the charging side of the radio, not 5. They use the same battery of a P7200.

Well, my bad. I have a dozen tri chem chargers, all with 4 pin battery contacts.
I had to buy yet another with 5 pins to charge a P5400. Now I may be werong, but the XG-100P also has 5 pin battery contacts.
So I guess not all unity radios use the same battery.

 

[splinter34]

XG-100P has 4 pin batteries...... P5400 is not a Unity radio. Xg-100P and the XG-100M are Unity radios.

 

[redbeard]

You are not going to unlock wideband.

Wideband disable feature prevents it. 'Unlocking' is as simple as having the disable feature removed. Similar to the Narrowband feature on other models.

 

[Teotwaki]

Well, my bad. I have a dozen tri chem chargers, all with 4 pin battery contacts.
I had to buy yet another with 5 pins to charge a P5400. Now I may be wrong, but the XG-100P also has 5 pin battery contacts.
So I guess not all unity radios use the same battery.

The 5 pin charger I bought by mistake is a CH-104560-007 Rev J and it sits in the garage

 

[Teotwaki]

That is an awful elusive manual. I have a full complement of desktop chargers and pockets, and been trying to build up all the charger documentation I can fin. So far, very incomplete.

I now have a physical copy of the manual MM-018439-001 for the version of the VC-4000 prior to the XP-100 radio.

 

[Teotwaki]

Back in February I purchased a XG-100M that was govt surplus from the USMC Yermo California rail yard. It was set up for some interesting 380-400 MHz trunking frequencies and P25. It has a number of the desirable features turned on.

So the radio had been waiting for me to order connectors, get a control head and and cables together and install it on my work-desk. Got it all set up last Saturday and I belatedly realized that output power seemed to be zero despite pulling what looked like normal current draw. Then I found that receive sensitivity was off by 50 dB.

My mistake was not performing very detailed testing when I first received it. Mea culpa. Now I need to figure out if this can be fixed or if it's become a parts radio.

PRCguy and I talked about checking the antenna connector and receive path for the VHF/UHF portion. I thought that I would also check receive sensitivity on the separate TNC low band connector. Turns out low band VHF was also showing significantly low sensitivity. Given that two separate receive paths have the same problem I don't think it is a Tx/Rx "relay" (pin diode) problem but something common to both unless somehow this thing was hit by lightning.

Redbeard doesn't think anything software or feature-wise can cause this problem. Possibly way off frequency or perhaps something common in the power supply to the RF board? At least on receive it seems to be on frequency

Without schematics (nonexistent?) it will require a lot of guessing to test the power supplies, especially with the way the radio is packaged.

I've never paid attention to the calibration data before but will try to look that over and compare to my good radios. Any pointers on the Cal files?

Any suggestions?

Thanks!

 

[wa8pyr]

Back in February I purchased a XG-100M that was govt surplus from the USMC Yermo California rail yard. It was set up for some interesting 380-400 MHz trunking frequencies and P25. It has a number of the desirable features turned on.

So the radio had been waiting for me to order connectors, get a control head and and cables together and install it on my work-desk. Got it all set up last Saturday and I belatedly realized that output power seemed to be zero despite pulling what looked like normal current draw. Then I found that receive sensitivity was off by 50 dB.

My mistake was not performing very detailed testing when I first received it. Mea culpa. Now I need to figure out if this can be fixed or if it's become a parts radio.

PRCguy and I talked about checking the antenna connector and receive path for the VHF/UHF portion. I thought that I would also check receive sensitivity on the separate TNC low band connector. Turns out low band VHF was also showing significantly low sensitivity. Given that two separate receive paths have the same problem I don't think it is a Tx/Rx "relay" (pin diode) problem but something common to both unless somehow this thing was hit by lightning.

Redbeard doesn't think anything software or feature-wise can cause this problem. Possibly way off frequency or perhaps something common in the power supply to the RF board? At least on receive it seems to be on frequency

Without schematics (nonexistent?) it will require a lot of guessing to test the power supplies, especially with the way the radio is packaged.

I've never paid attention to the calibration data before but will try to look that over and compare to my good radios. Any pointers on the Cal files?

Any suggestions?

Thanks!

I’d start by running it through a full alignment procedure to rule that out. If the tracking data is off, it could certainly cause similar issues.

 

[prcguy]

I’d start by running it through a full alignment procedure to rule that out. If the tracking data is off, it could certainly cause similar issues.

How do you run one through a full alignment? The maintenance manual shows the TCXO as the only available adjustment.

 

[Teotwaki]

I’d start by running it through a full alignment procedure to rule that out. If the tracking data is off, it could certainly cause similar issues.

Thanks! That's definitely a good thing to do. Is it in a manual somewhere?

 

[redbeard]

Apparently it is actually a supported radio on at least one of the current-gen autotuning service monitors. If they perform more steps than just the TCXO warp, I couldn't say from experience. Call some local shops to see who has the capability.

 

[Teotwaki]

Apparently it is actually a supported radio on at least one of the current-gen autotuning service monitors. If they perform more steps than just the TCXO warp, I couldn't say from experience. Call some local shops to see who has the capability.

I've been out of the 2-way radio shop scene too long and no longer have any contacts. Maybe I can look for a manual for an autotuning service monitor and see what it says.

 

[Teotwaki]

Here's one

R8000 SERIES
COMMUNICATIONS SYSTEM ANALYZER
AUTOTUNE USER GUIDE
Harris XG-100 Mobile

·TCXO Frequency
·TX Power
·Tx Analog Modulation
·Tx CTCSS/CDCSS Modulation and Composite Deviation
·P25 Phase 1 Tx Modulation (C4FM) Test
·Tx P25 Phase 2 Tx Modulation (TDMA) Test
·Rx Audio Level and Distortion
·RX Sensitivity (SINAD)
·P25 Phase 1 Rx Sensitivity (C4FM) Test
·P25 Phase 2 Rx Sensitivity (TDMA) Test

 

[Teotwaki]

There is a thread that says the radio has some sort of internal auto-cal mode to work with possibly factory alignment equipment

Harris auto calibration - Harris XG-100P Unity

My Harris XG-100P radio went in to auto calibration mode for maybe about 30 seconds then rebooted the radio and everything went back to working just fine since then no issues and never had any issues before the radio went in to auto calibration.

forums.radioreference.com

 

[Teotwaki]

There are some useful calibration clues in RPM2 maintenance help files

 

[Teotwaki]

Question: since this radio had a P-25 trunked system in its mission plan, is there any chance that the original owners used a command in OTAP to render the radio useless?

So far any Harris brochures I have found do not mention such a capability.

 

[Teotwaki]

I found the FCC's type acceptance document that has internal photos of the radios and boards. I'm sure some things have changed but still a useful file

 

[Teotwaki]

I used my HP8594E spectrum analyzer to take a look at the radio's output during transmit. To be safe I started with 100dB of inline attenuation looking across 50 MHz to 2 GHz in case there was power on an incorrect frequency. What I did find when narrowing up the bandwidth was a very attenuated signal (down 120dB) on the correct frequency.

 

[redbeard]

Question: since this radio had a P-25 trunked system in its mission plan, is there any chance that the original owners used a command in OTAP to render the radio useless?

So far any Harris brochures I have found do not mention such a capability.

They could kill it over the air but then it wouldn't work at all. This isn't that.