eHam

eHam Forums => Repeaters => Topic started by: KD9VV on November 19, 2013, 05:22:14 PM



Title: Reverse Burst
Post by: KD9VV on November 19, 2013, 05:22:14 PM
Been a amateur radio op for years, yet I've always wondered why (Reverse Burst) was never incorporated into repeaters and/or any stand alone amateur Xcvr?

The only reason I can think of is patents by Motorola?

Side note: I've noticed the Baofeng UV5R I recently purchased when used in DCS with "STE" turned on, acts alnost like reverse burst. Very nice for simplex ops.


Title: RE: Reverse Burst
Post by: K4JJL on November 23, 2013, 08:45:08 PM
Can't be a patent thing. Both GE and Kenwood commercial radios have it built in, as well.


Title: RE: Reverse Burst
Post by: N2HBX on November 25, 2013, 07:39:55 PM
I would venture to guess that most hams outside of the commercial two-way field aren't really familiar with reverse burst and what it does, thus the manufacturers don't see a need to incorporate it into their products.

73,
Larry, N2HBX


Title: RE: Reverse Burst
Post by: AA4PB on November 26, 2013, 05:17:40 AM
Is reverse burst still beneficial now that most decoding is done with solid state rather than mechanical reeds?



Title: RE: Reverse Burst
Post by: K4JJL on November 26, 2013, 08:02:33 AM
Is reverse burst still beneficial now that most decoding is done with solid state rather than mechanical reeds?

Most definitely.  The electronic reverse burst signals the squelch to close even before the TX drops.  It will shave off the squelch tail nicely.

I use all commercial radios for both portable, base and repeaters.  All have reverse burst turned on.  No reason not to.  I usually laugh at repeaters with squelch tails.


Title: RE: Reverse Burst
Post by: KD9VV on November 26, 2013, 09:55:24 AM
Can't be a patent thing. Both GE and Kenwood commercial radios have it built in, as well.

The operative word being "commercial"

I'm not aware (or convinced) that Kenwood or GE commercial radios are not licensing the rights (be it intellectual or technical) to PL technology from Motorola?

Essentially, I find it archaic that amateur (FM) radio does not incorporate such a wonderful feature as CO squelch IMO is annoying. With DSP technology now in full bloom, it would or should be a easy addition.


Title: RE: Reverse Burst
Post by: K4JJL on November 26, 2013, 11:33:12 AM
Can't be a patent thing. Both GE and Kenwood commercial radios have it built in, as well.

The operative word being "commercial"

I'm not aware (or convinced) that Kenwood or GE commercial radios are not licensing the rights (be it intellectual or technical) to PL technology from Motorola?

Essentially, I find it archaic that amateur (FM) radio does not incorporate such a wonderful feature as CO squelch IMO is annoying. With DSP technology now in full bloom, it would or should be a easy addition.

The do use different names, and the technology does vary slightly.  GE's "Channel Guard" uses a 135 deg phase shift and a 160 ms delay in its "Squelch Tail Eliminator" circuit.  Motorola uses 120 deg shift.

Also, the patent for this technology are long expired.  While the name is trademarked, I'm sure the technology is not licensed now, since it's that old.


Title: RE: Reverse Burst
Post by: KD9VV on November 26, 2013, 01:27:15 PM

Can't be a patent thing. Both GE and Kenwood commercial radios have it built in, as well.

Also, the patent for this technology are long expired.  While the name is trademarked, I'm sure the technology is not licensed now, since it's that old.
[/quote]

Fair enough..Then can anyone answer my initial question why it is not incorporated into FM amateur radio?
Surely the answer is not cost.


Title: RE: Reverse Burst
Post by: K4JJL on November 26, 2013, 03:02:24 PM
Most people who ask me to program their FM radio are completely unaware that it even does CTCSS on the RX.  When I tell them I turned it on, they ask, "What's that supposed to do?"  After explaining that, the next question is, "Why doesn't it squawk when the repeater unkeys anymore?"  After I explain that, they ask, "Can you make it squawk again?  I like it that way."

Based on that, I'd attribute it to low demand.  Hams aren't even using CTCSS squelch, let alone even aware of what reverse burst does.  They actually like the squawks.  These are the same people who have the Chinese handhelds that spout out Engrish whenever a button is pressed.  Soooo annoying...


Title: RE: Reverse Burst
Post by: AA4HA on November 26, 2013, 03:17:46 PM
The only reason I do not use CTCSS on receive is for when I am traveling and run across another repeater on the same frequency but using a different CTCSS tone for access to the repeater input. I can at least listen in.


Title: RE: Reverse Burst
Post by: K4JJL on November 27, 2013, 05:52:10 AM
The only reason I do not use CTCSS on receive is for when I am traveling and run across another repeater on the same frequency but using a different CTCSS tone for access to the repeater input. I can at least listen in.

That's the beauty of a monitor button on a Motorola radio (or a hangup box).


Title: RE: Reverse Burst
Post by: KS4VT on November 28, 2013, 05:11:06 AM
The only reason I do not use CTCSS on receive is for when I am traveling and run across another repeater on the same frequency but using a different CTCSS tone for access to the repeater input. I can at least listen in.

And not all repeaters transmit CTCSS (PL), so you might see activity with a signal strength meter or LED, but obviously you won't hear squat unless you are in carrier squelch.


Title: RE: Reverse Burst
Post by: KV4BL on December 10, 2013, 11:19:39 AM
I'm one of those hams who actually likes the squelch tail at the end of a transmission.  For one thing, it sounds like a real radio did did back in the 60's, when I was first interested in them because of the ht's the local police were just getting.  For another, it sounds better than a lot of those annoying and dorky "courtesy tones" which let you know the other guy has quit transmitting, in case you didn't hear the faint click and were not watching the S-meter on the screen when he un-keyed.  I never understood why people move Heaven and Earth to eliminate the squelch tail from the end of transmissions through a repeater and then replace it with an even more annoying "courtesy" tone. 

Either way, if someone bothers to PL their repeater on the input AND output and leave it that way, rather than letting it blow noise across the air all day or night, endlessly key and un-key, or other signs of sloppy engineering, it is all good IMHO. 

73,

Ray  KV4BL


Title: RE: Reverse Burst
Post by: WB6DGN on March 24, 2014, 12:22:26 AM
Quote
I never understood why people move Heaven and Earth to eliminate the squelch tail from the end of transmissions through a repeater and then replace it with an even more annoying "courtesy" tone.

1.  I don't "move heaven and earth to eliminate the squelch tail", I merely check one box in the programming while entering my data.  Hardly a strenuous endeavor.

2.  I have no control over those "dorky" courtesy tones, that's the purview of the repeater owner/trustee, not the individual user however I do agree that they are annoying and useless and more than a little "CBish".

3.  Almost equally annoying to me is that "also dorky" carrier drop out delay that, in the tube days, served a useful purpose but, in today's world of solid state base stations/repeaters no longer serves a useful purpose other than to encourage "kerchunking" endlessly on some repeaters.  That's another relic of a bygone era that needs to go away sooner rather than later.

4.  And, finally, there's voice ID and endless "announcements".  All repeater controllers that are capable of doing those need to be recycled for their precious metal content as soon as possible with NONE of the proceeds going to the repeater club that installed them.

So, there you have MY wish list.  Now, just wait 'till 'they' make me king!

Tom


Title: RE: Reverse Burst
Post by: NJ1K on March 24, 2014, 04:50:11 AM
Dorky courtesy tones, hmmm...

Those dorky tones on my system actually have an important purpose.  My repeater is part of a linked system and call routing is done with different PL tones.  The "dorky" courtesy tones indicates from what part of the network the call originated from and to where it is routed.  Change PL tone, your call gets routed to a different path in the network and you get a different "dorky" courtesy tone.

If not for the networked system, I would have no courtesy tone or hang time.


Title: RE: Reverse Burst
Post by: WB6DGN on March 24, 2014, 01:38:52 PM
Quote
Dorky courtesy tones, hmmm...
 

DON'T SHOOT THE "MESSENGER"!  My comment (in quotes) was merely a semi-sarcastic reference to a PREVIOUS POST.
In your case, as you noted, the tones serve a necessary purpose so they probably wouldn't even be described as "courtesy tones" in much the same way as the MDC tone warns to pause before talking to complete the data transfer and the "talk permit" tone in some trunking systems notify the user when talk may commence.
And...you seem to concur with my OPINION about the subject by noting that you, too, would not use them if they were not necessary for the proper operation of your system.
Geesh!  Why is everybody so ready to look for an argument these days??????????????????
Tom


Title: RE: Reverse Burst
Post by: W2NAP on March 24, 2014, 06:14:25 PM
Quote
Dorky courtesy tones, hmmm...
 

DON'T SHOOT THE "MESSENGER"!  My comment (in quotes) was merely a semi-sarcastic reference to a PREVIOUS POST.
In your case, as you noted, the tones serve a necessary purpose so they probably wouldn't even be described as "courtesy tones" in much the same way as the MDC tone warns to pause before talking to complete the data transfer and the "talk permit" tone in some trunking systems notify the user when talk may commence.
And...you seem to concur with my OPINION about the subject by noting that you, too, would not use them if they were not necessary for the proper operation of your system.
Geesh!  Why is everybody so ready to look for an argument these days??????????????????
Tom

us Muricans like to argue.

I use courtesy tones as well signaling if the transmission came from repeater in, remote input, or voip.
Voice id is ok IMO if it is used to just ID the damn machine, can't stand the machines that announce every little thing. or tosses a ID out when nobody is using the machine.
hang time, at first I didn't use it. but got annoyed at the idiots chunking it to see if machine was on... set it to 2 seconds then someone got the bright idea in the early morning hours to sit for hours on end just chunking to make the machine come up classic chunk,tone,drop chunk,tone,drop (had a archive of some idiot doing that for 2 hours one morning at 2AM.) so I set the hang to 10 sec.. which stopped the chunker and over time dropped it back to 5 seconds. (seems anything under 3 sec would bring the chunker out) 5 seconds is to long for him to wait. so that is where it stayed.


Title: RE: Reverse Burst
Post by: NJ1K on March 27, 2014, 07:18:25 PM


us Muricans like to argue.

I use courtesy tones as well signaling if the transmission came from repeater in, remote input, or voip.
Voice id is ok IMO if it is used to just ID the damn machine, can't stand the machines that announce every little thing. or tosses a ID out when nobody is using the machine.
hang time, at first I didn't use it. but got annoyed at the idiots chunking it to see if machine was on... set it to 2 seconds then someone got the bright idea in the early morning hours to sit for hours on end just chunking to make the machine come up classic chunk,tone,drop chunk,tone,drop (had a archive of some idiot doing that for 2 hours one morning at 2AM.) so I set the hang to 10 sec.. which stopped the chunker and over time dropped it back to 5 seconds. (seems anything under 3 sec would bring the chunker out) 5 seconds is to long for him to wait. so that is where it stayed.
[/quote]

Mine uses voice ID but also tells in voice when the machine is on back-up power and what the back-up battery voltage is when it's on back-up power.  I don't care for general anouncements but when the repeater is limping along I do want to know. 


Title: RE: Reverse Burst
Post by: KG4RUL on May 04, 2014, 06:02:34 AM
Hang time serves a useful purpose.  Our ARES repeaters are set up with an open squelch tail that allows someone, who does not have the tone set up, to make listeners aware that they are trying to transmit, which can be useful in an emergency situation.  Other users can then let that operator know what the required tone is.  Of course, this assumes that the operator can actually program his/her rig.  All I can say to someone who is bothered by this - there are other repeaters.


Title: RE: Reverse Burst
Post by: AF6D on May 23, 2014, 02:28:18 AM
Quote
Dorky courtesy tones, hmmm...
 

DON'T SHOOT THE "MESSENGER"!  My comment (in quotes) was merely a semi-sarcastic reference to a PREVIOUS POST.
...
Geesh!  Why is everybody so ready to look for an argument these days??????????????????
Tom

Tom,

I absolutely agree with your assessment. I watched a casual thread go completely south just because someone felt the need to "defend" the use of tones to route patching. I come from the school of thought that unless a post adds in a positive manner it shouldn't be a post :) Maybe I shouldn't be posting :D

I think that the "dorky courtesy tones" are the silly, animated, not natural d-wop (like water dripping) or "I am the KING!!!" idiot type courtesy tones. Personally I don't use courtesy tones and can link three MSF 5000's together just fine. I use a 2 second hang time. Our COR drop corresponds with our PL drop so someone yelling for help can ride the coat tail -- or know their radio well enough to put it into tone search. 99% of our users like our setup. The link repeaters have a zero hang time. Controllers like the Arcom RC-210 have kerchunk filters but the more annoying jammer uses DTMF. The Arcom RC-210 allows DTMF passing to be turned off. I pissed a group of misfits off that know that I have an HT next to me at all times and DTMF away. We also encode/decode and the user may decide whether or not to listen to distant repeaters. Those of us that live on the mountains that our repeaters are on can always hear the repeaters 100 miles away and decode sure is nice.

Even more annoying are the new hams (new hams, nothing wrong with being new if you are realistic) that buy a $30 Chinese made HT and think that they can conquer the repeater world with their marginal signals. The Motorola MSF 5000 is a terrific repeater and can hear a mouse fart 120 miles away using an HT inside of a metal car with a rubber ducky dummy load antenna. But one should not assume that every repeater is located at over 6,000 feet as are mine. As such we limit reception to 1uV (-107dBm) and avoid the grunge talker all together. "Your repeater sucks!" No sir, your HT can't hold the machine. Please use a real radio with a better antenna. A 5 watt HT with even a cheap scanner antenna will do so much more than the cheap Chinese radios flooding the market. Stick a 1/4 wave whip on a mag mount and talk away! No repeater can cover 100% of its contour with 40 over S9 in 100% of the locations. we set our power output to as closely match our input as possible. No time for alligators. But some people like beaconing regardless of Part 97. Go figure.