VHF Quantar frequency issue (TX no locking)

[arbitergvadam]

Hello.
I wanted to see if anyone has encountered an issue simular to mine on a quantar.
Upon getting a VHF frequency coordinated of TX 152.2775, RX 157.5375 I programed the VHF R2 Quantar with the appropriate frequencies and was immediatly met with no TX lock and exiter failure. I then when back into the programming and swapped the 2 frequencies to RX 152.2775, TX 157.5375. Upon writing and rebooting the quantar it turned on worked fine. Then i set the frequencies back to TX 152.2775, RX 157.5375 and same issue.
I just wanted to make sure the VHF R2 quantar should be able to do both types of configurations or is there something I am missing?

 

[prcguy]

Hello.
I wanted to see if anyone has encountered an issue simular to mine on a quantar.
Upon getting a VHF frequency coordinated of TX 152.2775, RX 157.5375 I programed the VHF R2 Quantar with the appropriate frequencies and was immediatly met with no TX lock and exiter failure. I then when back into the programming and swapped the 2 frequencies to RX 152.2775, TX 157.5375. Upon writing and rebooting the quantar it turned on worked fine. Then i set the frequencies back to TX 152.2775, RX 157.5375 and same issue.
I just wanted to make sure the VHF R2 quantar should be able to do both types of configurations or is there something I am missing?

I would read the config with CPS and see if it matches what the station actually is. What is the power level set for? If the station power level alignment is off it could be faulting due to high power. You could also read the fault logs and see what's going on.

 

[N4KVL]

prcguy is on the money. Quantar were never made to have codeplugs read out, modified and blown back in. Weird things can happen. Use one of the default demo codeplugs in the RSS directory and modify to suit your needs from there.

SIlly question, but have you verified that in the codeplug you have Freq Ref set to "Internal - Standard", or "Internal - High Stability" if you have the TCXO module installed. There is a chance that the unit came out of a site that utilized an extrnal frequency reference.

When was the last time the station was aligned with a calibrated service monitor? If the TX reference oscillator is too far out of spec, the PA won't lock. Depending on how long it has been sitting out of use, you can also try reseating the modules.

 

[prcguy]

prcguy is on the money. Quantar were never made to have codeplugs read out, modified and blown back in. Weird things can happen. Use one of the default demo codeplugs in the RSS directory and modify to suit your needs from there.

SIlly question, but have you verified that in the codeplug you have Freq Ref set to "Internal - Standard", or "Internal - High Stability" if you have the TCXO module installed. There is a chance that the unit came out of a site that utilized an extrnal frequency reference.

When was the last time the station was aligned with a calibrated service monitor? If the TX reference oscillator is too far out of spec, the PA won't lock. Depending on how long it has been sitting out of use, you can also try reseating the modules.

Within reasonable limits and after alignment a Quantar can be read and programmed over most of its range with only the rx front end needing alignment. I've taken a VHF Quantar from the 160s and 170s down to the upper 2m range and power, deviation and P25 waveform were fine. The exciter gets aligned over the entire operational range and the RF power alignment is usually good for most if not the entire band. But you have to read a known good and aligned unit to do this and if any modules were swapped or the code plug is from another life with different hardware it will need a complete alignment.