GRE PSR-500 for OASIS - Any Tips?

[HowD]

I am using Win500 to program a GRE PSR-500 scanner with data pulled directly from the RR DB via the Web download feature on Win500.

I realize that the GRE PSR-500 is an older scanner, and that simulcast is likely the main issue with reception of the Milwaukee County OASIS (P25) system.

That said, does anyone have any settings tweaks or advice to improve locking onto the voice channel that is in use? I can lock onto the control channel and the decode rate will vary between 80-92%. However when scanning the scanner will stop on a voice channel but only for a bit, with choppy audio.

In comparison, the WISCOM (also P25) system comes in with excellent reception (99% decode on the control channel) and I do not have the same issue. Not sure from a technical standpoint (I believe the modulation type is different) but there is a definite difference in that system as compared to OASIS.

I considered deleting the alternate control channels to force using only the current CC but if the CC changes I would have to reprogram the CC. Also, I don't have any issues with WISCOM which is using 18 different CCs in my configuration.

 

[GTO_04]

Deleting the alternate control channels will do absolutely nothing to help your simulcast reception. Most WISCOM towers are no simulcast and that is why you have better reception on that system. The limited ability of the PSR-500 (I own one too) to monitor simulcast systems is just a limitation you will have to live with. You can try moving it to different locations in your house and believe it or not that may help a little bit.

GTO_04

 

[OpSec]

I am using Win500 to program a GRE PSR-500 scanner with data pulled directly from the RR DB via the Web download feature on Win500.

I realize that the GRE PSR-500 is an older scanner, and that simulcast is likely the main issue with reception of the Milwaukee County OASIS (P25) system.

That said, does anyone have any settings tweaks or advice to improve locking onto the voice channel that is in use? I can lock onto the control channel and the decode rate will vary between 80-92%. However when scanning the scanner will stop on a voice channel but only for a bit, with choppy audio.

In comparison, the WISCOM (also P25) system comes in with excellent reception (99% decode on the control channel) and I do not have the same issue. Not sure from a technical standpoint (I believe the modulation type is different) but there is a definite difference in that system as compared to OASIS.

I considered deleting the alternate control channels to force using only the current CC but if the CC changes I would have to reprogram the CC. Also, I don't have any issues with WISCOM which is using 18 different CCs in my configuration.

OASIS is a multi-site simulcast system, where there are many tower sites transmitting the same signal on the same frequency at the same time. WISCOM in the area is multicast, meaning each site is transmitting on discreet frequencies that aren't shared.

Your scanner is having a hard time decoding the simulcast signal because the radio is having a hard time interpreting the incoming overlapping signals. If you put a really bad antenna on your scanner, it may get better as in some cases reducing the signal the scanner can hear significantly will help...but it will probably never be great.

 

[HowD]

Thank you both for the replies. This explains it well.

 

[jaspence]

Antenna and location are the best things to try on that radio. Due the age and electronic design of the time it was made, simulcast was not a consideration.

 

[HowD]

Ah, now I see in the RR DB the way to tell if a system is simulcast is via the site name--it's spelled out right there.