ZumSpot - RX audio - raspy sounding

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KA9MGS
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Joined: Mon Mar 25, 2019 3:44 pm

ZumSpot - RX audio - raspy sounding

Post by KA9MGS » Mon Apr 01, 2019 4:22 pm

Hi All!

I'm really enjoying the Pi-Star application and greatly appreciate the efforts by the Pi-Star team to put this all together - hats off to you!

I've recently purchased the ZUMSpot and configured it for operation on the Brandmeister network where it connects to the BM Server in Texas (I'm located in Chicago IL). When listening to the traffic on TAC310, for example, the audio sounds a bit raspy almost like listening to someone talk through a spinning desk fan (but not quite as extreme). The RX voice is totally intelligible but I've heard examples on youtube DMR demo clips where the "raspy" audio issue is not present or at least not detectable by my hearing.

Stations with "0" for packet loss and BER will still sound raspy to me and I've attempted to tweak the TXOffset on the Pi-Star but to no useful effect.

I'm wondering if there is any way to improve the audio quality or at least determine the root cause. Any advice would be greatly appreciated!

I currently use a Connect Systems CS-700 to interface with the ZUMSpot. Could this be an issue with the CS-700 (I know this radio isn't exactly a high quality rig)?

Thanks and 73

Chris.

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KE0FHS
Posts: 1078
Joined: Wed Apr 11, 2018 8:40 pm
Location: Colorado, USA
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Re: ZumSpot - RX audio - raspy sounding

Post by KE0FHS » Mon Apr 01, 2019 6:31 pm

Are you connected to your network via WiFi? Is so, check your Wireless Information in the Wireless Configuration section of the Configuration page. I'm not sure what the healthy range is, but I experience good audio, and see settings like:
Bitrate : 72.2 Mb/s
Transmit Power: 31 dBm
Link Quality : 63/70
Signal Level : -47 dBm

Another thing I'd suggest trying is a different BrandMeister server. Maybe try 3101 in New York.

Finally, yes, it could be the radio. See if a friend has a different radio you can test with.
73, Toshen, KE0FHS
Playing with Pi-Star (unofficial notes about setting up and using Pi-Star):
https://amateurradionotes.com/pi-star.htm

KA9MGS
Posts: 4
Joined: Mon Mar 25, 2019 3:44 pm

Re: ZumSpot - RX audio - raspy sounding

Post by KA9MGS » Mon Apr 01, 2019 7:44 pm

Yes, the ZUMSpot is connected to my home WiFi router that's located in the same room as the ZUMSpot. I'll check the health range information, haven't tried that yet - Thanks!!

Yesterday I did try a different BM server as an experiment. It made no difference to the RX audio so I left it there.

Also, yesterday, I ordered the Anytone UV-878 HT. If the CS-700 is the issue then perhaps I'll have my answer with improved audio performance on the new HT.

Thank again for responding to my post.

73

Chris.

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KE0FHS
Posts: 1078
Joined: Wed Apr 11, 2018 8:40 pm
Location: Colorado, USA
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Re: ZumSpot - RX audio - raspy sounding

Post by KE0FHS » Mon Apr 01, 2019 9:54 pm

The 878 is a nice radio. I think you'll enjoy it. Good luck!
73, Toshen, KE0FHS
Playing with Pi-Star (unofficial notes about setting up and using Pi-Star):
https://amateurradionotes.com/pi-star.htm

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