LA Sheriff's Analog Conventional Frequencies on SDS100 - Reception and Intermod Issues

[dmullen1373]

Hey guys,

I'm starting a new thread to target my fellow Angelenos with SDS100s who are experiencing intermod and other reception quality issues.

I'd love to hear of any tweaks that you used to get things to work better. I keep hearing dispatched calls going out on t

 

[werinshades]

Hey guys,

I'm starting a new thread to target my fellow Angelenos with SDS100s who are experiencing intermod and other reception quality issues.

I'd love to hear of any tweaks that you used to get things to work better. I keep hearing dispatched calls going out on t

Probably should post in California forum, might have better luck.

 

[Ubbe]

I'm starting a new thread to target my fellow Angelenos with SDS100s who are experiencing intermod and other reception quality issues.

RF problems are very much dependent of the exact location. But only using a signal generator giving one single frequency will also create all kinds of intermod and bleed overs. The SDS scanners does not have as good receiver as Unidens other scanners pre-SDS. If you have simulcast issues then other choises are few. Only if you scan from home can you expect a non-SDS scanner to work if you experiment with different antenna types.

Here you can listen to a recording of the audio signal from different frequencies on a SDS100 when a signal generator are sending a signal on a totally different frequency.

SDS100/SDS200: - Global Auto Filter Vs. Global Attenuation

I was reading through some previous posts and I am unclear on the difference between Global Auto Filter and Global Attenuation. What I have been doing recently is scanning groups of frequencies in sequential order to determine what DMR Color Codes are being used. On a few UHF frequencies in...

forums.radioreference.com

/Ubbe

 

[iMONITOR]

Hey guys,

I'm starting a new thread to target my fellow Angelenos with SDS100s who are experiencing intermod and other reception quality issues.

I'd love to hear of any tweaks that you used to get things to work better. I keep hearing dispatched calls going out on t

Search RR for forum post regarding the use of programmable filters in the SDS series of scanners.

 

[dmullen1373]

Search RR for forum post regarding the use of programmable filters in the SDS series of scanners.

Thank you, but I've tried them all in addition to IFX on the frequencies with issues. What's worked 100% is attenuating every single frequency used by the department. Drastic, yes, but also effective. I feel like there has to be a better way, though, as some of the distant stuff that I used to receive is now buried under the attenuator.

 

[prcguy]

What part of LA (city/neighborhood) is the problem showing up?

Thank you, but I've tried them all in addition it IFX on the frequencies with issues. What's worked 100% is attenuating every single frequency used by the department. Drastic, yes, but also effective. I feel like there has to be a better way, though.

 

[dmullen1373]

What part of LA (city/neighborhood) is the problem showing up?

I'm in Glendora and as a result Dispatch Ch. 6 for Walnut and San Dimas just bleeds through everything else. Thanks for replying! I'd be curious to know what you've done to try and mitigate this issue.

 

[iMONITOR]

What are you using for an antenna and what bands are you are experiencing problems with? It can make a lot of difference.

 

[prcguy]

I'm not as familiar with that part of LA County but your not that far from the LASD Easter Ave transmitter site near the 710 and 10 fwy. You may also be in a blast zone for Mt. Wilson and some other nearby mountain top sites. I don't have any problems receiving any LASD in my area south of you.

Does dispatch ch 6 just come through all the time and where it doesn't belong in complete transmissions or does it come and go mid sentence like its mixing with another signal and the interference comes and goes with that other signal?

At least in your area you can take comfort knowing Burro Canyon shooting range is always close by when the interference becomes too much to handle.

I'm in Glendora and as a result Dispatch Ch. 6 for Walnut and San Dimas just bleeds through everything else. Thanks for replying! I'd be curious to know what you've done to try and mitigate this issue.

 

[cmdrwill]

You may also be in a blast zone

"blast zone" I like that. Yup the RF sinkhole.... Los Angeles County.

What are you using for an antenna?

Dispatch 6 has several transmitter locations including at San Dimas and Walnut stations and on on Via Verde.right in your back yard,
Can you spell receiver overload.....

 

[werinshades]

Thank you, but I've tried them all in addition to IFX on the frequencies with issues. What's worked 100% is attenuating every single frequency used by the department. Drastic, yes, but also effective. I feel like there has to be a better way, though, as some of the distant stuff that I used to receive is now buried under the attenuator.

Did you try changing the modulation to FM and setting the volume offset to +2 or +3?

 

[Anderegg]

My SDS's are as bad at intermod and signal bleedover as my old MR8100...I get 800MHz MDT data from adjacent frequencies on my local 800 analog trunking system, that I NEVER have gotten on any other scanner I ever owned, Uniden, or Whistler, GRE, Radio Shack, nothing...really bad.

Paul

 

[dmullen1373]

Yeah I'm actually returning it and going to fight to get my $$ back on the NXDN and DMR upgrades, too. The Bearcat Warehouse has been totally understanding so that's cool. I bought the upgrades straight from Uniden, though. I'm telling you I'll dispute those charges every week until they concede. This thing should have never made it past the QC guys in wherever it's made. It's terrible. This thing is am embarrassment to Uniden.

 

[dmullen1373]

What are you using for an antenna and what bands are you are experiencing problems with? It can make a lot of difference.

I'm using the Remteonix 800MHz antenna (but I've tried a Diamond 77A ad well as an MFJ.) I get the same behavior on all of them.