SteveShannon's Content - Page 131 (2024)

Nice. Yes, you probably could run it once a day as a cron. If the pi is never restarted and if rc.updatenodelist just runs and sleeps then eventually you’ll have the same problem, but it may take nearly two years!

The real question I have is if rc.updatenoelist runs to completion and breaks out of its loop or if it continues running. If it exits eventually then it shouldn’t be gobbling up memory and you could run it as a cron more frequently. It was only because you had like 544 instances running and sleeping that you had problems (that’s what I think anyway).

5 hours ago, chasedog1 said:

A Vertex tech sold me the repeater after he serviced and did an alignment. everything seems to be back correctly. The HT only receives on the frequency the repeater is on, I go a few mhz up or down and its gone. it does stop when I remove the HT's antenna

I don’t think anything is wrong. You shouldn’t expect a handheld radio not to have its receiver circuitry overwhelmed by a high power transmitter nearby.

2 hours ago, fpcaptain said:

That seems like the best or at least only thing to do to keep from chewing through memory.

Do any instances of rc.updatenodelist run at all? Are there any sleeping? I think I read somewhere that a module called “dial” might call it once.

Is it possible there’s a problem in the extnodefile itself?

Remove the antenna on your handheld. Does it still happen?

Is the case correctly assembled to the repeater? What about the duplexer? Cables?

I suspect your handheld is just not very good at rejecting interference from the repeater. Typically you’d never use a handheld in the same room as a repeater.

6 minutes ago, chasedog1 said:

I go farther away from the repeater and the signal drops off to nothing unless I ask someone to key it. This happens on all channels no matter what. It happens in repeat or base mode as if there is a leak powering the xmitter with very low power. I am going to try to obtain a signal field strength meter and take more readings.

Is there a transmit LED or display on the repeater (or even a wattmeter on the output) that indicates when the transmitter is transmitting?

Does it stop if you power down the repeater? (I know that probably sounds like a dumb question and maybe it is. )

15 hours ago, chasedog1 said:

I have the repeater setup and when I turn on a HT the repeater seems to be dead keying or transmitting but I am not doing anything. It does it on all channels all the time. I can key the HT and hear myself then key the mic on the repeater and hear my self with the HT.. any ideas ?

Help me understand the proximities involved and the exact nature of your concern. When you’re in the same room as the repeater with one of your handhelds, no matter what channel you tune the handheld to you hear whatever the repeater transmits.

Also, using an identical handheld, when you go farther away from the repeater the handheld only hears the repeater on the correct channel.

Is that a correct description?

5 minutes ago, gortex2 said:

AUXCOMM is a sit in class. As said alot of the basic ICS can be done online for free. They take about an hour each max. Less time if you have been in public safety. The AUXCOMM course is a good bridge between Public Safety and Amateur Radio but is only as good as you take out of it. The last 3 I have been part of only about 2 guys actually took anything out of the class and are active in other parts of public safety also. If your in public safety and a ham its an ideal course.

Thanks!

Are you sure you haven’t changed anything in the code?

In particular look at the post immediately above your first post where WRLJ719 talks about thecall to rc.updatenodelist. Also, his post appears to have a misspelling “rc.updatenodeist” rather than “rc.updatenodelist”. Nothing makes a person more aware of spelling than programming.

It looks like cron is spawning new instances of “rc.updatenodelist” which runs and then goes to sleep, over and over and over, each time eating up valuable resources until there are none left. I suspect eitherrc.updatenodelist needs to exit gracefully, rather than sleeping, or something needs to be fixed in crontab. I doubt it needs to run very frequently anyway, but it should exit each time.

That link to the stackoverflow question that I pasted above has other suggestions for diagnosis.

You probably do have the 3b+ but that shouldn’t matter.

So, look at where you were when you followed this instruction:

”Changeyour crontab -e to run rc.updatenodelist”

and make sure you did it correctly and that you included the asterisk as pointed out by WRLJ719.

My rule on metal roofs is to get on them as seldom as possible and to rope off if the pitch is uncomfortable.

At that height, and running the cable the way you have to you’re possibly going to lose a lot of signal just in the coax. Be sure to use the best coax you can. Here’s a website that has several charts showing coax losses. Be sure to look at the 450 MHz values:https://www.w4rp.com/ref/coax.html

Second, I’m not sure that either of those antennas will get you the performance you might hope. Try putting that mag mount with either Nagoya onto a metal pie plate on a painters pole out in your yard first, or even on the roof of your car. Does it work well enough? If so, then maybe get on the roof. If it doesn’t work then you’ve saved yourself a trip.

I was wrong to focus on problems like shorts or opens. KAF6045 is correct. With RG58 you lose half of your power every thirty feet. Sometimes you can up for that by placing a decent quality antenna up in the air, but with a bad antenna, a bad cable, or a weak signal lack of quality will really bite you.

Borrowing a VNA from someone can tell you if you have the kind of problem I was overly fixated on before (opens and shorts), but won’t tell you if your antenna has lousy performance.

If an HT with a Nagoya has good performance but an antenna up in the air doesn’t you have every right to be suspicious of both the antenna and the cable. I’ll include a link to a website with performance charts for various cables. Be sure to look at the frequency you’re using. The closest frequency will probably be 450 MHz. Because GMRS is slightly higher, the losses through cable at GMRS frequencies will be even worse, but not a lot. Every 3dB loss means half of the remaining power, so 10.6 dB loss costs about 90% of the power. That’s for 100 feet. At 35 feet you lose over 3.7 dB so you probably lose 55% of the signal each direction. That’s substantial and enough to make it difficult to know if the antenna works or not. Of course everything adds up. It helps to start with something you know works and then try one thing at a time to see where you can get some improvements.

Coax losses site I mentioned:https://www.w4rp.com/ref/coax.html

8 minutes ago, WRUU925 said:

I'm happy but I got my GMRS license Friday night and finally was able to log in here tonight and just wanted to say hi.

Welcome!!

6 minutes ago, WRED210 said:

I'll try a different cable and a shorter run of the same kind and see if that makes a difference. Thanks for your input.

You really can rule out almost everything by swapping things out. It’s a quick and easy way to troubleshoot.

2 minutes ago, WRED210 said:

Could it be the 35 ft of cheap rg58 coax? Would that cause enough loss to lose reception?

If there’s actually something wrong with it, such as a short between the center conductor and the shield, yes. Or if the center conductor is broken or disconnected from the radio or antenna.
Those kinds of problems can be present in the antenna as well.
Try a different cable.

7 minutes ago, WRED210 said:

Well.... I mounted the fiberglass 1/2 wave on a mast about 23 high (about 10 ft above garage roof), and not near that steel covered patio... and get zero reception. It tries to break squelch, but I hear nothing. The nagoya whip on the same HT gets some reception. Could it be that this cheap amazon antenna is just junk?

4 minutes ago, Cpch64 said:

Reporting Back:

Thumbs up on the "Comet GP-6NC GMRS/FRS Commercial Dual-Band VHF/UHF Base Vertical Antennas GP-6NC"!!

It bridged the gap on the TX side and better RX. I'm now able to talk with both repeaters 45-58 miles away during daytime hours in which i could not do before.

Many thanks for all the information!!

That’s great news!

Thanks for the update.
Steve

1 hour ago, wayoverthere said:

https://web.psrg.org/psrg-voting-system/

Here is something I stumbled across on the ham side of the table, that seems to provide a good description of what's going on behind the scenes and the gear they're using..don't know if it's any help

I have a friend who is on that system and who has good results.

50 minutes ago, JohnE said:

GPS would be for simulcasting to sync the transmitters timing. Also said transmitters would have to have a high stability XO to lock it on frequency.
You are need a comparator or something that works like one. seeing as you are using IP everything should come back to one "computer" and select the site w/best RSSI and as it moves it goes to the next. IIRC there was a HAM that had some you tubes on it. I think it was in relation to a simulcast set up.
hope this was some help

Gps could also be used at each receiver to time tag signals as received, which could then be used to ensure the comparator is comparing synchronized portions.

Marc,

I’m sure you have already seen this but maybe it will help provide background. This is from repeater-builder:

“A good voting system is completely transparent when it's working properly - you can't tell it's there except by the superior coverage. Obviously the voter has to be voting identical simultaneous signals, which is why using VOIP (voice over IP, a.k.a. the Internet) as a link to bring in the audio from one or more outlying receive sites usually does not work - there is too much delay and jitter, causing the voter at one instant to be voting the noise between two words on channel one and voting the middle of the previous word on channel two. Manually adding a fixed delay to the one receiver in an IP network does not work either, as the per-path internet packet switching delay is not consistent, even within one transmission, and definitely not from one transmission to the next. Note that there is a lot of incentive to "fix" this characteristic, and a revision of this paragraph may be needed at some point as the technology advances.”

1 hour ago, fpcaptain said:

Thanks for the response. I thought this may be the case as when I looked it up I was reading this but didn't know what was causing it. I have a rasp pi 3b and a sd card that is 32 gig if I remember right and I installed the hamvoip image and did what was said above. So I guess I'm not sure what the fix will be or if anyone else has had this happen who has tried this way on hamvoip but I am looking for the cure.

Thanks

A memory leak like that will eventually cause a stack overflow no matter how much memory you have. The stackoverflow forum link I posted has some suggestions for how you can see what processes are being forked and never exit or killed. Then you (or a programmer if you’re not) will have to figure out why those calls aren’t exiting freeing up their memory. Things to look for are incursion (when a function calls itself), or calling cron from within a loop. Since cron seems to be at the heart of this issue that’s what I would start with. Cron is a scheduler. It only needs to be called once for each scheduled task or fork. It typically shouldn’t be called over and over with the same parameters unless you kill it before calling it. (Which would be sloppy coding!)

So, check and see which processes are running. If you have a whole bunch of some dig into why.

Good luck,

Steve

56 minutes ago, WRKC935 said:

Steve, I would look into the ICS training online. That's where I got mine.

Have 100 700 and 907

Got all of them online.

Thanks! I appreciate the help.

27 minutes ago, gortex2 said:

ITs very are specific for sure. I hear about clubs that are very active and involved in public safety and into new technology. Again I read and hear about them. I have yet in 20 years come across one of those groups in working all over the North East. I was a member of 2 different RACES groups up north at different times. Both held nets and "drills" but anytime either got asked to actually help with something no one was ever available. Unless it was a 9-4 scheduled event you never got any of them to leave the donut coffee shop and actually assist. I'm another 1/4 century ham and am saddened at the state of ham radio now. I got my career in part with ham radio. Where I am now the county has no races/ares or any ham involvement. I talked to the 911 director and his take is they have a TLMR system and the State also does. He sees no need for them and if he needs them he said he plans to call the state. I wish I could find that "group" of active involved hams but in 25 year I have not.

21 minutes ago, gortex2 said:

I miss the "old" GMRS days. It was much simpler and no one was on my repeaters unless I wanted them on them. And when they were they had a real radio.

Get off my lawn!

28 minutes ago, WRKC935 said:

Alright,,, damn. Make one little comment about ham radio membership not being what it once was and y'all are looking to burn me at the stake.

So lets preface this. In 2024, 2 years away, I will be renewing my ham license for the second time. Which of course means in total I will have been a ham for 30 years at that point. And I have sat and watched the technical abilities of hams decline over the years. Now, do I think it will kill ham radio? No, I don't. And I will NOT be one of the asshats like those that sat around complaining about the dropping of Morse Code and how that would turn ham into CB radio, or that the decline in actual radio knowledge will do it in either. But in 30 years, I have met a bunch of hams, some of them are damn knowledgeable. But I am not seeing that as much any more. And I am not hearing serious technical discussions being had on the air. Of course, I don't hear much of anything other than on HF any more. And I am not seeing much interest in learning about radio in the ham community either. The move has been to DMR hotspots where the sum total of the RF communications begin and end in less than 20 feet. Using the Internet to bridge the distance. So as long as you can program a radio and configure a hotspot, you can communicate. For all of 20 feet. You realize you don't even NEED an antenna to talk that far. And yes, I do find all that disheartening. And what really gets me is all that demand for knowledge and wanting to learn is right here in GMRS and the service is limited to less than 1 Mhz of total frequency allocation and is ONLY wideband FM. We have no SSB, digital, packet, none of that. And we are fine with it. And I am good with it too. I just wish since there is so much interest in radio and how it all works here, that we have one little bit of one band to mess about with. Mind you, GMRS ain't ham radio. Never will be. I just wish that ham radio had the sort of participation that GMRS is now enjoying.

I don’t want to burn you at the stake, I promise! Amateur radio needs people who have your experience and knowledge. I understand your concerns, but I’m seeing ham radio differently. I’m a member of a couple groups for homemade antenna building, a couple groups for digital HF modes like FT8, an antenna modeling group, and even a group dedicated to test equipment. I see nobody on any of those groups who self identified as a Baofeng waving question memorizer, but I would not be surprised if some started there and grew into more technically interested hams.
I’m excited also about how we make use of GMRS, because that’s also very useful.
I think that a person’s perspective really depends on their surroundings and it sounds like you’re not enjoying the same surroundings as I am.