UV-5R - "quieting" under open squelch

[royldean]

Those of you on the UV-5R yahoo group will recognize this issue (already tried to rectify it there):

using a couple of Baofengs for ham sat communication (a UV-5R and an F8HP), but the 5R exhibits strange behavior when used to monitor the downlink:

Even with squelch set at 0 (full open - even after reprogramming the squelch values with Chirp), the HT "quiets" when the downlink signal gets strong - sounds exactly like it is CLOSING the squelch! While this is happening, the antenna picture is displayed on the screen. It happens for about a second, and then the transmission will resume, with the "cutting out" occuring every 5 seconds or so on a strong downlink signal. Needless to say, this is very annoying as I lose about 20% of the downlink communication.

This happens on both 2m and 70cm downlinks. It does not happen at all on the F8HP. It also does not happen at all if I tune the 5R to the local repeater frequency. Even adjust for doppler doesn't seem to affect it.

I can overide the "cutting out" by holding the "MONI" button, but obviously this is not something I can do during a 10 minute sat pass. I have also tried the narrowband setting (doesn't do anything), as well as the "save" set to "off".

Any suggestions?

 

[wyShack]

check if your dual receive is on -that would do it.

 

[royldean]

"TDR" set to "off"

essentially, any option that is available in the menu is set to "off"

 

[KD8DVR]

Yes. No tdr. I set the uplink as my transmit frequency and
The downlink accordingly. I set a few channels to compensate for Doppler shift. Got me several contacts, before ao27 and ao51 died.

We need more FM birds.

Sent from my LG-D631 using Tapatalk

 

[talkpair]

Supposedly these radios respond to a 55 Hz shutoff tone sent by other UV-5R's if the Squelch Tail Elimination option is "ON"

You might want to check this option and make sure it's OFF.

I don't if this will resolve the problem, but it may be worth investigating.

 

[KD8DVR]

Interesting factoid: this function HAS to be enabled to allow the standard DCS. Shutoff tone. Most radios use the DCS shutoff tone anytime DCS is used. Not Baofeng. I use DCS on my Echolink micronode.

That definitely could be an issue with the op"s issue, if it expects a disconnect tone, and none is found.

Sent from my LG-D631 using Tapatalk

 

[nd5y]

Supposedly these radios respond to a 55 Hz shutoff tone sent by other UV-5R's if the Squelch Tail Elimination option is "ON"

You might want to check this option and make sure it's OFF.

Menu 35 STE only enables or disables transmitting the STE tone and DCS 134.4 Hz turnoff code.
There is no way to disable receiver muting on the 55 Hz STE tone except by programming a receive DCS code.
If this satellite, or anything else that isn't using DCS, happens to have a low level hum or tone at around 55 Hz then Baofeng and other CCRs that use this STE method will mute the receiver and you will hear nothing unless you hold down the monitor key.

 

[royldean]

If this satellite, or anything else that isn't using DCS, happens to have a low level hum or tone at around 55 Hz then Baofeng and other CCRs that use this STE method will mute the receiver and you will hear nothing unless you hold down the monitor key.

This is very interesting. I think this very well may be the issue.

 

[KD8DVR]

This is very interesting. I think this very well may be the issue.

Yes. Very good point.

AntiSquid Disclaimer: All posted content is personal opinion only and may not imply fact or accusation.

 

[nd5y]

I posted the following on the Baofeng yahoo group a few years ago.

There seems to be some misunderstanding about STE (Squelch Tail Elimination) as implemented in the UV-5R.

I have done some testing and experimenting and figured out exactly what Menu 35 STE actually does. Some people believe it is the same PL/CTCSS reverse burst as implemented by Motorola, GE, Kenwood, and other commercial radios and repeaters. This is not true (except when using DCS/CDCSS. See #2 below). Some people believe it is just a short duration dead carrier with no tone. This is also not true. Baofeng STE is actually a form of anti-PL (or anti-CTCSS) using a tone of approximately 55 Hz.

Here is what is actually happening:

1. If you are using PL/CTCSS encode or carrier squelch (Menu 13 T-CTCS set to any tone or OFF), and Menu 35 STE ON, the radio sends a 55 Hz tone for about 1/4 second when you release the PTT key. Setting Menu 35 STE OFF disables this function.

2. If you are using DCS/CDCSS encode (Menu 12 T-DCS set to any code) and Menu 35 STE ON, the radio sends a 134.4 Hz tone, for about 1/4 second when you release the PTT key. This is the standard CDCSS turnoff code and should be compatible with any system that uses DCS/CDCSS. Setting Menu 35 STE OFF disables this function.

3. The important part:
The UV-5R receiver responds to the 55 Hz STE tone by muting the receive audio (also known as anti-PL or anti-CTCSS). This happens even in carrier squelch mode (Menu 10 R-DCS and Menu 11 R-CTCS both OFF). This is the important part. Whenever the receiver detects a 55 Hz tone, it mutes the audio for as long as the tone is present and for about 1/2 to 3/4 second after the tone and/or carrier drops. However, it appears that if the 55 Hz tone is sent while a CTCSS tone is present, the receiver doesn't seem to detect the 55 Hz tone and doesn't mute. This might be because of something in my test setup.

Here is the cool part. If your radio PL/CTCSS encoder or repeater controller is capable of custom non-standard tones and you transmit a 55 Hz tone, then Baofeng radio users will not be able to hear anything at all, even if they turn all tones off and have the squelch wide open (set to 0) the 55 Hz tone still mutes the receiver. The only way around it is to continuously hold down the Monitor (MONI) key. It might be a neat thing to do on April 1.

I don't know how many other manufacturers use this STE method. All of the above also applies to a Wouxun KG-UV2D. The only difference is that the Wouxun doesn't have a menu option to turn STE off. Maybe it is a Chinese industry standard; possibly a relatively new one. I know that none of the Alinco, Icom, Kenwood or Yaesu amateur radios I have owned in the past had this and I don't think the current ones do or it would be advertized.

Repeaters and commercial receivers with tone decode will mute the receiver when they lose the tone; that is if the tone stops or the transmitter stops without making a reverse burst. Apparently on some systems this happens quickly enough that it fools people into believing that Baofeng radios have real PL reverse burst.

I still have not been able to determine what Menu 36 RP-STE and Menu 37 RPT-RL do. They don't seem to have any effect at all in any combination with Menu 35 STE or in any combination of PL, STE tone or dead carrier.

UPDATE:
Menu 36 RP-STE disables the receiver from coming back on (keeps it muted) for up to ~1 second after PTT release; in other words it increases transmit to receive turnaround time.

Menu 37 RPT-RL disables CTCSS or DCS decoding for up to ~1 second after the delay time set by Menu 36 RP-STE. If no receive tone is set then Menu 37 has no effect. Settings 1 and 2 appear to be the same as OFF and have no effect. Settings 3 to 10 increase the decoder disable time from ~50 mS to ~1 S.

 

[royldean]

Hmm, this makes it more interesting. Because the satellite repeaters that I am accessing do indeed required a PL tone on the uplink, so according to what you wrote above - the 55 Hz tone shouldn't be "recognized", correct? That would throw a wrench in the works.....

 

[nd5y]

All I know is a 55 Hz tone will mute Baofeng receivers even if the squelch is off (set to 0) and pressing the monitor key is the only way to unmute it if a 55 Hz tone is present.
From what you are describing it sounds like your receiver muting problem is consistent with receiving a 55 Hz tone but it could be something else causing it.
I don't know if the satellite has 300 Hz high pass filtered transmit or receive audio or makes a 55 Hz tone for some reason.

 

[KD8DVR]

All I know is a 55 Hz tone will mute Baofeng receivers even if the squelch is off (set to 0) and pressing the monitor key is the only way to unmute it if a 55 Hz tone is present.
From what you are describing it sounds like your receiver muting problem is consistent with receiving a 55 Hz tone but it could be something else causing it.
I don't know if the satellite has 300 Hz high pass filtered transmit or receive audio or makes a 55 Hz tone for some reason.

That could mean people could develop a n anti Baofeng device to exclude said radios from repeaters.

AntiSquid Disclaimer: All posted content is personal opinion only and may not imply fact or accusation.

 

[KD8DVR]

I posted the following on the Baofeng yahoo group a few years ago.

The HT to HT mode... Does that have yet another tone that's used to quiet the receiver.

All this is interesting. I actually use these functions almost all the time. It doesn't hurt anything. I use Baofengs for my Echolink node and I have a totally silent receiver.

AntiSquid Disclaimer: All posted content is personal opinion only and may not imply fact or accusation.

 

[nd5y]

The HT to HT mode... Does that have yet another tone that's used to quiet the receiver.

All this is interesting. I actually use these functions almost all the time. It doesn't hurt anything. I use Baofengs for my Echolink node and I have a totally silent receiver.

No. There are only two modes that do the same thing.
1. 55 Hz tone that only works in CSQ or CTCSS.
2. 134.4 Hz tone that only works when encoding or decoding DCS. in the industry this is called the DCS Turnoff Code.

The check box in Chirp programming software that says Squelch Tail Eliminate (HT to HT) is the same as Menu 35 STE in the radio. It enables or disables transmitting the above tones but has no effect on receive.


I use a FT-7800R as my node radio. It has PTT, COS and audio connections on the rear packet data connector. When you feed transmit audio into the connector, it isn't high pass filtered like mic audio so the low frequency tones don't get stripped. This can be good or bad. One thing I tried was creating a 200 mS long 55 Hz tone with Audacity in the format EchoLink likes for audio files and use it as EchoLink's courtesy tone. It works great at quieting Baofeng and Wouxun receivers unless the 7800 is also transmitting PL.

 

[KD8DVR]

I just use DCS for my node. The turnoff tone is enabled, which is effective on My stuff now. Earlier Baofengs, for some reason, didn't like DCS, especially when working with other brands.

Projects with this could really get another thread rolling good

AntiSquid Disclaimer: All posted content is personal opinion only and may not imply fact or accusation.

 

[Mike5701]

Wouxun kguv8d

"TDR" set to "off"

essentially, any option that is available in the menu is set to "off"

I'm having the same issue with my wouxun kguv8d I'm not able to receive a transmission unless I'm holding the monitor button but I'm able to transmit just fine on the same frequency only when holding monitor is when I'm able to hear
But I cloned from my buddies wouxun so all the settings of the same and match his

 

[Mike5701]

Interesting factoid: this function HAS to be enabled to allow the standard DCS. Shutoff tone. Most radios use the DCS shutoff tone anytime DCS is used. Not Baofeng. I use DCS on my Echolink micronode.

That definitely could be an issue with the op"s issue, if it expects a disconnect tone, and none is found.

Sent from my LG-D631 using Tapatalk

Hey I have a wouxun kg uv8d and I'm not able to receive transmission unless I'm holding the monitor button but I'm able to transmit just fine. I clone from my buddies works on and all the setting seem to match so I'm not sure what's wrong I'm able to transmit on the same frequency but I cannot receive unless holding monitor and I can't find any answers nowhere please help