BCD436HP/BCD536HP: P25 simulcast receiption sometime need a helping hand to start

[Icanhearit]

I live in CA Bay Area (East Bay) and have strong local P25 signal and does not seems suffer the simulcast multipath issue, I mean when I get reception, is normally pretty clear without garble or cutting off etc.

But what is strange, is may be 1/3 o time , upon the scanner is powered on, which is normally set to have only (say) FL1 as active (in which all are selective digital channels from same site), the scanner starts scanning but remains quiet until I put my hand around it as if to pick it up but really just wrap around it, after few seconds (perhaps when a channel is active) then everything comes to life, I do not need to keep putting my hands there, the scanner becomes very chatty.

This symptom may also happens when I switch from FL1 to FL2 (full of analogue channels) and back to FL1 (analogue FL never suffer the issue). This symptom may show up while I remain on FL1 (but rarely). This pretty much rules out physical ill contact issue.

My Antenna is REM-842s (optimized for 800-900Mhz though my FL1 channels are pretty using upper 700Mhz), reception signal strength is not likely an issue though. I toggled digital threshold mode, threshold level settings, seems they make no difference. The scanner is made in 2021 (according to the serial# decoding).

Anyone observe the same symptom? Seems a firmware issue.

 

[maus92]

The REM 842 is a tri band antenna; the REM-810S is the antenna optimized for 700/800.

Your body is becoming an inductive part of the antenna system. Coupling is not an usual phenomenon.

Why does moving your hands in front of the TV or radio antenna influence the reception?

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[Icanhearit]

The REM 842 is a tri band antenna; the REM-810S is the antenna optimized for 700/800.

Your body is becoming an inductive part of the antenna system. Coupling is not an usual phenomenon.

Why does moving your hands in front of the TV or radio antenna influence the reception?

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Thanks for replying, I have a REM-810S on the way that FedEx seems is using a cow to transport it. I will see what happened next week upon getting it. But even with REM842S, the signal is very strong, as long as it start moving (for either REM842 or stock rubber duck one)) . I would think if my body becomes part of antenna, the reception will stop once I step away, but as long as it start, no reception issue with strong signal.

 

[maus92]

Thanks for replying, I have a REM-810S on the way that FedEx seems is using a cow to transport it. I will see what happened next week upon getting it. But even with REM842S, the signal is very strong, as long as it start moving (for either REM842 or stock rubber duck one)) . I would think if my body becomes part of antenna, the reception will stop once I step away, but as long as it start, no reception issue with strong signal.

Sounds more coincidental, but you are the one experiencing it. The 436 is not designed specifically to receive simulcast signaling, thus it can do some weird things depending on its location wrt to transmit sites. I doubt the problem is with the radio (other than its design.) Getting the REM-810 has the potential to making your issue worse as it will have a bit more gain at its designed frequency range - you actually want to attenuate the signal a bit so that the radio is only receiving one site, which can be a bit tricky. Good luck.

 

[JoeBearcat]

Also make sure your squelch is not open. That can cause 'weird things' to happen. Usually a setting of 2 or higher is adequate.

 

[Icanhearit]

Also make sure your squelch is not open. That can cause 'weird things' to happen. Usually a setting of 2 or higher is adequate.

yeah it is 2 or 4, most of the time, is 2.

Thanks no biggie, just a small nuisance, once give it a palm hug , then everything goes until probably another power cycle, or switch away then back to the favorite list ( 25-30% probability).

BTW, cannot stop ranting FedEx sucks. the antenna, sitting in the 15 miles away FedEx facility still has no pending delivery date. After 4 consecutive days fails its promised delivery, it now stop giving me any delivery promise, and disappear from apps "to me list"

 

[JoeBearcat]

One thing to try is to program a 'dummy system' and let the scanner scan between the two to see if that changes anything.

 

[mc48]

My 436 just sits there at times after I download to it then magically just starts receiving again. Has nothing to do with me touching or holding it,
I just set it down and after a minute or two (sometimes longer) the signal comes back, it may be simulcast related, but it's a completely random issue for me.

 

[Icanhearit]

My 436 just sits there at times after I download to it then magically just starts receiving again. Has nothing to do with me touching or holding it,
I just set it down and after a minute or two (sometimes longer) the signal comes back, it may be simulcast related, but it's a completely random issue for me.

Thanks, so basically we have the same symptom. I stop short of mentioning it may come back to life by itself after variable minutes (but not necessarily just right after new downloading). The "helping hand" will shorten the speechless period to few seconds as the site (East Bay Regional Communications System (EBRCS) Trunking System, Multiple, California - Scanner Frequencies) is busy, seldom quiet for over 20 seconds, 24x7.

 

[maus92]

Weather. Solar radiation. Time of day. Location of the scanner radio. All can affect and interact with simulcast (and multicast) reception. Don't expect a change in firmware will address the issues you are experiencing - it's the design of the scanner receiver that is the root cause.

 

[werinshades]

My 436 just sits there at times after I download to it then magically just starts receiving again. Has nothing to do with me touching or holding it,
I just set it down and after a minute or two (sometimes longer) the signal comes back, it may be simulcast related, but it's a completely random issue for me.

Thanks, so basically we have the same symptom. I stop short of mentioning it may come back to life by itself after variable minutes (but not necessarily just right after new downloading). The "helping hand" will shorten the speechless period to few seconds as the site (East Bay Regional Communications System (EBRCS) Trunking System, Multiple, California - Scanner Frequencies) is busy, seldom quiet for over 20 seconds, 24x7.

Simulcast reception issues on a non-SDS scanners is what you're both describing. The only option is an SDS100/SDS200.

 

[twjr80]

Simulcast reception issues on a non-SDS scanners is what you're both describing. The only option is an SDS100/SDS200.

I thought the same thing until I got a 700\800MHz yagi antenna and pointed it at the nearest radio tower. Works like a charm.

 

[maus92]

I thought the same thing until I got a 700\800MHz yagi antenna and pointed it at the nearest radio tower. Works like a charm.

For those with the ability to install a yagi, they can mitigate simulcast issues to varying degrees. Doesn't work if you need a mobile solution.

 

[werinshades]

I thought the same thing until I got a 700\800MHz yagi antenna and pointed it at the nearest radio tower. Works like a charm.

That is a simulcast issue, you just purchased a yagi, took the time to install it while an SDS scanner would have saved alot of the time.

 

[JoeBearcat]

My 436 just sits there at times after I download to it then magically just starts receiving again. Has nothing to do with me touching or holding it,
I just set it down and after a minute or two (sometimes longer) the signal comes back, it may be simulcast related, but it's a completely random issue for me.

Typical simulcast behavior. There are a number of threads with possible solutions. Don't discount the paper clip antenna trial and the attenuator.

 

[twjr80]

That is a simulcast issue, you just purchased a yagi, took the time to install it while an SDS scanner would have saved alot of the time.

And cost A LOT more money. No thank you.

 

[ofd8001]

I always suggest taking the scanner to about 1/4 of a transmitter site to see if the audio clears up. If so, that is pretty definitive that simulcast distortion is the culprit.

The key to improving simulcast decoding, and thus audio clarity, is to "worsen" reception. Receiving multiple sites causes "confusion" with incoming X's and O's being out of sync.

 

[werinshades]

And cost A LOT more money. No thank you.

On the low end of purchasing a 436hp, Yagi, cable, and a mast your savings are being cut into for the purchase price of an SDS100. You might not be receiving as well as you think, because silence doesn't mean inactivity but lack of proper decoding. I know this by comparison before I sold my 436. This solution isn't very practical, and I've seen others swear up and down the mast pole how good this works etc. An SDS scanner resolves all these issues, and has been well documented. To each their own, good luck.

 

[KevinC]

On the low end of purchasing a 436hp, Yagi, cable, and a mast your savings are being cut into for the purchase price of an SDS100. You might not be receiving as well as you think, because silence doesn't mean inactivity but lack of proper decoding.

I agree. Without a known good receiver to compare to you don't know what you are missing

 

[mc48]

I know in my case it receives everything my 2 SDS100's and SDS200 receive, the issue is it just sits there and receives nothing when I return from downloading to it or turn it on. I use mine to record a system 24/7 and it decodes it almost as well as the SDS radios.