Batboard

Hi Group,
For all the Quantar gurus out there , I am working on my Amateur repeater system. Currently testing 3 Quantar base stations in mixed mode operation all tied together with an AstroTac 3000 comparator. All seems just fine, P25 and analog all repeat . I came across this anomaly. When setting up analog levels I discovered that one quantar exhibited an audio notch around 1Khz. Only one Quantar has this notch. I cannot find any reference to there being a notch in the audio path. If I check out the other Quantars there is no notch and 1Khz audio freq passes just fine. I monitored the audio at the wireline input Line 1 and the 1Khz is there but not on the TX output. Suggesting the comparator is not the culprit. I was curious is this modifiable , can it be turned on or off or change the notch freq ? I cannot see any thing in RSS that controls this notch. It would be nice to use this to notch out audible ID's.

Any insight would be helpful and educational

Thanks
Larry

additional info: notch freq is indeed centered at 1Khz

Oh hey Larry!

1kHz is the tone used as a status tone with the ASTROTAC 3000 in analog mode. Much like SPECTRATAC uses 2175Hz, Harris uses 1950Hz, well, ASTROTAC uses 1000Hz.

If you are voting in analog mode using the ATAC, I would expect a notch to be present. I would look at the wireline configuration with regard to voting on both stations and see if there is anything different.

It's also possible you have different revision wireline cards, station control boards, or firmware (or both, or all three).

It may be that if you set the wireline type to v.24 only, you'll lose the notch. But then you won't be doing voting in analog, only digital.

Maybe the modulation compensation is maladjusted?