Users may not create topics, posts, or private messages containing or relating to the following material (especially pertaining to Motorola copyrighted software, unless you want Motorola to come along and shut this site down):

  • Listing for sale or trade of, or links to sites offering for sale or trade of, or giving away, Radio
    Service Software (RSS) or Customer Programming Software (CPS)
  • Profanity, pornography, defamation, or slanderous remarks directed towards any individual or entity
  • Commercial advertising (except in the Batboard Vendors forum, as approved by the Admin/Mod Staff)
  • Any other items which may be deemed as offensive

If any topics, posts, or private messages containing or relating to the aforementioned material are brought to the attention of the Admin/Mod Staff, they will be deleted.

Additional FAQ items appear here in Forum Rules. Please review them for posting guidelines and further clarification.

Notch filtering in Quantar

The General forum is where users can discuss any topic regarding Motorola communications equipment - hardware, software, etc. There are also several focused forums on this board, so please take the time to ensure that your questions doesn't fall into one of those categories before posting here!

Moderator: Queue Moderator

Posts: 74
Joined: Sat Oct 22, 2005 2:05 pm

Notch filtering in Quantar

Postby ldanna » Sun Apr 08, 2018 9:21 am

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


Posts: 74
Joined: Sat Oct 22, 2005 2:05 pm

Re: Notch filtering in Quantar

Postby ldanna » Sun Apr 08, 2018 10:11 am

additional info: notch freq is indeed centered at 1Khz

User avatar
Posts: 3465
Joined: Tue Mar 19, 2002 4:00 pm

Re: Notch filtering in Quantar

Postby d119 » Mon Apr 09, 2018 10:15 am

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.

Posts: 48
Joined: Fri Jun 02, 2006 7:23 pm

Re: Notch filtering in Quantar

Postby RFI-EMI-GUY » Fri Jul 13, 2018 10:01 pm

Maybe the modulation compensation is maladjusted?

Return to “General Motorola Solutions & Legacy Radio Discussion”

Who is online

Users browsing this forum: No registered users and 14 guests