Quantar Questions

[ElroyJetson]

A few basic Quantar questions. I have almost zero experience with Quantars, and none that falls within my assigned task.

VHF quantar, 150.8 to 174 bandsplit.
Customer wants to use it as a 2 meter repeater.
Will the preselector tune into the 2m band and deliver rated sensitivity?

I've checked its programming and though all the data is right, upon receiving a transmission it unmutes for about a quarter of a second, mutes, and never attempts to go into transmit mode. It's a basic conventional model without options.

Suggestions?

 

[mikewazowski]

What does the station log say?

 

[AK4PY]

The R2 VHF Quantar stations will TX from 144 - 148MHz fine, but the RX VCO will not lock somewhere just below 146MHz usually. I have heard of someone using a screwdriver to get the RX VCO to lock on a lower frequency, but I have not had to do it myself. Every R2 VHF Quantar I have ever programmed for 146MHz and up operation has always had full output and full RX sensitivity with no problem.

 

[prcguy]

Most range 2 VHF Quantars will work fine down to about 146MHz tx and rx with some working into the 144MHz range. The preselector tunes fine, it’s the tx low VCO and possibly the rx VCO that can go out of lock and when near the edge tx deviation may not be predictable. There is a mod to add or replace the ferrite slug in the VCO tuning coil so you can get the VCO voltage within acceptable range anywhere in the 2m band.

 

[n7maq-1]

It all comes down to revisions, I use to sell a lot of used "split" VHF band units RX-R1 and TX-R2 that I was getting from England and they worked great for all the ones that went to the ham bands (P25 or Analog). IIRC they had Epic 2 SCM.

I have also come across some full R2 units with "shorter" SCM's (I want to say Epic 3's) that I could not get the TX VCO aligned for enough TX AU in the ham band.

Of course there units out there with trunking only SCM's, but very rare on VHF.

I do have a full VHF R1 that I don't use anymore, I should think about moving it along.

 

[ElroyJetson]

Station log? Yeah, right. It's a used repeater, I don't know where it came from, no logs included, I'm just the tech trying to check it out.

Still not sure why it's not trying to actually function as a repeater.

 

[firefive76]

Station log? Yeah, right. It's a used repeater, I don't know where it came from, no logs included, I'm just the tech trying to check it out.

Still not sure why it's not trying to actually function as a repeater.

The station log is read with the RSS.

 

[N4DES]

Did you try to make it a repeater on a dummy load in the native 155.xxx frequencies to see if the non-repeat issue is or is not frequency dependent?

 

[ElroyJetson]

Yes, it was connected to a dummy load and tested on its programmed frequencies, with a suitably programmed radio. Its behavior is exactly as previously described. A relay clicked, it unmuted for a split second, then went silent, and there was never any indication it went into transmit.

 

[KevinC]

Yes, it was connected to a dummy load and tested on its programmed frequencies, with a suitably programmed radio. Its behavior is exactly as previously described. A relay clicked, it unmuted for a split second, then went silent, and there was never any indication it went into transmit.

Analog or P25?

 

[ElroyJetson]

Analog, no options, a base model unit as far as I've been able to determine.

Read via the DOS based RSS. First time I've used RSS in years.

 

[prcguy]

Yes, it was connected to a dummy load and tested on its programmed frequencies, with a suitably programmed radio. Its behavior is exactly as previously described. A relay clicked, it unmuted for a split second, then went silent, and there was never any indication it went into transmit.

Is it programmed as a base station? If so it may have an external T/R relay and it won’t repeat. The T/R relays often get stripped off when surplussed. If it’s programmed as a repeater and you send it the programmed rx signal and tone/NAC it should show the receiver is active and it should transmit. If it’s broken it may not receive with no indication of a problem but if the transmitter is broken and it tries to repeat you should get a failure indication on the exciter module.

 

[Project25_MASTR]

I've taken one R2 down that low. When tested, 12 dB SINAD was -119 dBm instead of the -122 dBm in 150 MHz. Preselector banded down fine though.

The thing is, I reprogrammed that Quantar yesterday to add a North Comm controller to it and the VCO doesn't want to lock anymore. Alignment got it to lock so I'll try realigning it again, I just didn't have time to mess with it yesterday.

 

[prcguy]

I've taken one R2 down that low. When tested, 12 dB SINAD was -119 dBm instead of the -122 dBm in 150 MHz. Preselector banded down fine though.

The thing is, I reprogrammed that Quantar yesterday to add a North Comm controller to it and the VCO doesn't want to lock anymore. Alignment got it to lock so I'll try realigning it again, I just didn't have time to mess with it yesterday.

Love those Northcomm controllers.

 

[wgbecks]

Love those Northcomm controllers.

Not to hijack the thread, but has there been any changes to either the hardware or the firmware of the Northcomm controllers such
that they retain user configuration upon a power cycle instead of returning to factory defaults?

 

[prcguy]

Not to hijack the thread, but has there been any changes to either the hardware or the firmware of the Northcomm controllers such
that they retain user configuration upon a power cycle instead of returning to factory defaults?

No, they will still loose configuration. But it should be possible to battery backup the controller.

 

[ElroyJetson]

It's in repeater mode. I checked every setting on every page in the RSS, I'm not seeing anything that would keep it from operating as a repeater. There is no second channel programmed, but it does have a multiple PL table. One PL, 118.8, and one DPL, 615 I think.

 

[prcguy]

It's in repeater mode. I checked every setting on every page in the RSS, I'm not seeing anything that would keep it from operating as a repeater. There is no second channel programmed, but it does have a multiple PL table. One PL, 118.8, and one DPL, 615 I think.

Does it transmit when you push the shift and local PTT button?

 

[ElroyJetson]

no it doesn't.

 

[AK4PY]

If it cannot be locally keyed in the original 150+ MHz range with the shift and PTT buttons then you have a station with a problem that needs to be addressed before moving forward. That doesn't sound like programming/alignment. It sounds like a parts issue. You should try an alignment before giving up, though. Also, the Windows software is much better than the old DOS RSS you are using. You can read the station logs with the Windows software. I am unsure if you can read the logs with the DOS RSS. The logs should have a clue as to what is wrong.