P25 decode problem on AS2?
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P25 decode problem on AS2?
Do I have a problem with my new AS2?
I a Johnson 5100 and an AS2 VHF this weekend. I don't have the programming cable for the AS2 but, using my freq counter, I was able to determine the TX freq of one of the modes strapped for P25. I programmed that into the 5100 (yeah... FPP baby!) and set the RX NAC to F7E.
When I key the AS2, I get the ID of the AS2 on the display of the 5100 and it does decode the TX audio. The problem is that it is "pulsing" like once a second or slightly faster. It's like it's a clocking problem or something. The audio is clean for the second or so between resync's.
Could this be a problem with the AS2? I know the EFJ-5100 is good because I used it on P25 all weekend at Dayton.
Thanks...
I a Johnson 5100 and an AS2 VHF this weekend. I don't have the programming cable for the AS2 but, using my freq counter, I was able to determine the TX freq of one of the modes strapped for P25. I programmed that into the 5100 (yeah... FPP baby!) and set the RX NAC to F7E.
When I key the AS2, I get the ID of the AS2 on the display of the 5100 and it does decode the TX audio. The problem is that it is "pulsing" like once a second or slightly faster. It's like it's a clocking problem or something. The audio is clean for the second or so between resync's.
Could this be a problem with the AS2? I know the EFJ-5100 is good because I used it on P25 all weekend at Dayton.
Thanks...
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I just tried it with about 25yds of separation between the radios and I've still got intermittant decode on the Johnson. It's rythmic. A second (maybe shorter) of decode followed by a pop of sorts and then decode again.
It does the same thing if I switch to secure on the AS2 only the decoded audio is obviously scrambled.
It does the same thing if I switch to secure on the AS2 only the decoded audio is obviously scrambled.
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I haven't aligned it. I don't have a service monitor, let alone the alignment jig.
Heck, I don't even have an AS programming cable. :)
I found a mode that was IMBE, hit the PTT and then read the TX freq on my freq counter. I programmed the EFJ up for RX on that freq. That's all of the testing I've done.
Once we get the appropriate programming cable for the AS, I will be able to shoot a mode in where I know all of the details and we'll see if it still has problems. If it does, I'll have to get someone to align it for me and see if that fixes the issue.
Heck, I don't even have an AS programming cable. :)
I found a mode that was IMBE, hit the PTT and then read the TX freq on my freq counter. I programmed the EFJ up for RX on that freq. That's all of the testing I've done.
Once we get the appropriate programming cable for the AS, I will be able to shoot a mode in where I know all of the details and we'll see if it still has problems. If it does, I'll have to get someone to align it for me and see if that fixes the issue.
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I got it from w4wtf but, other than that, I don't know exactly where the radio came from. I don't think it's a whore-flashed AS2 though. The other WTF can answer that though.
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Coolness. I don't have a service monitor but, I can probabably find someone who does have one.r0f wrote:Hey John,
The value of alignment can't be undermined. It's the most important contributing factor (besides having recent firmware) to astro performance.
You don't require the test-jig btw. Just a programming cable, SMA->BNC adapter, and a service monitor.
You will adjust the oscillator warp (tx frequency), the deviation balance, the deviation, and power output. That's it. Very simple. No frills.
In deviation copensation balance adjustment (F4 in service), key the radio and measure the low tone. Then key with the high tone, and match the deviation to the low tone.
In deviation (F5 in service), set it for 2.83 KHz, or as close to that as you can get.
power and warp are something even the TIM could figure out.
Oh, and Panik is nuts. So are his prices. The guy has lost touch with the market.
Am I going to need DOS based Astro RSS to do the alignment? I've got Astro 25 Tuner but, I if I need the RSS flavor, I'm gonna have to track someone down who has the appropriate RSS to help me align it.
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i could not agree more, every time i see that guy at a hamfest (dayton/orlando etc) i make sure to give him the fingertvsjr wrote:Just to make things very clear: Fuck Panik. I wouldn't give him a penny if he had the last ASTRO radio on earth. He's fucking nuts, to boot.mr.syntrx wrote:Panik? He charges a mint for that shit.
Don't just limit yourself to a 1200S - I've heard of fleaBay having COM-120B's, 1600's, and 294x's for prices that break my heart.K8TEK wrote:Yeah, If only I could afford an IFR 1200Sr0f wrote:power and warp are something even the TIM could figure out.
Any of those would do for a simple alignment.
Now, of course, if you want to get fancy....
But if you cannot afford a 1200S, you cannot afford a 2975 or 3900.
I have been considering selling my spectrum analyzer for a service monitor... but it would kill me to give up a 22ghz hp spectrum analyzerWowbagger wrote:Don't just limit yourself to a 1200S - I've heard of fleaBay having COM-120B's, 1600's, and 294x's for prices that break my heart.K8TEK wrote:Yeah, If only I could afford an IFR 1200Sr0f wrote:power and warp are something even the TIM could figure out.
Any of those would do for a simple alignment.
Now, of course, if you want to get fancy....
But if you cannot afford a 1200S, you cannot afford a 2975 or 3900.
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tvsjr wrote:Fuck Panik.
tvsjr wrote:Fuck Panik.
tvsjr wrote:Fuck Panik.
tvsjr wrote:Fuck Panik.
Oh, and the alignment procedure Shaun posted is absolutely correct. Couple of minor revisions, though:
1.) When adjusting TX power and both sets of deviation settings, start with the highest test frequency and work your way down. On the deviation balance, you may have to go through it a few times before you get all the test frequencies matched up.
2.) If the deviation limit is way off, you'll need to go back and re-adjust the deviation compensation.
Ouch. What a choice. However, you could even do the simple alignment with a spec-an if it has the ability to demodulate the signal or tell you the deviation of the signal.FLECOM wrote: I have been considering selling my spectrum analyzer for a service monitor... but it would kill me to give up a 22ghz hp spectrum analyzer :ve4uo:
I'm glad I've not had to pay for my equipment.
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Rub it in why dontcha....Wowbagger wrote:Ouch. What a choice. However, you could even do the simple alignment with a spec-an if it has the ability to demodulate the signal or tell you the deviation of the signal.FLECOM wrote: I have been considering selling my spectrum analyzer for a service monitor... but it would kill me to give up a 22ghz hp spectrum analyzer
I'm glad I've not had to pay for my equipment.
On another note...there where a bunch of 8920/21's at Dayton this year.
I will always place the mission first.
I will never accept defeat.
I will never quit.
I will never leave a fallen commrade
I will never accept defeat.
I will never quit.
I will never leave a fallen commrade
You'd let Cowthief take your anal virginity for a 1600 and you know it.tvsjr wrote:Yeah, but why would you want any of that junque, when you could have an 8921 instead? :baby:Wowbagger wrote:Don't just limit yourself to a 1200S - I've heard of fleaBay having COM-120B's, 1600's, and 294x's for prices that break my heart.
As to what you'd do for a 3900....
Let's just say it's the Dirty Sanchez of test equipment, shall we?
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Bah. I had the opportunity to buy a 1900 - took the 8921 instead. The buffering when using the spec-an/TG sucks on the 1600s, 1900s, and even the 2975s. It's way too long. The 8921 shows changes near-instantaneously, IFR notsomuch.Wowbagger wrote:You'd let Cowthief take your anal virginity for a 1600 and you know it.
As to what you'd do for a 3900....
And, the 1600/1900 UI isn't just user-unfriendly... it's user-hostile, IMO. I think you wrote that code so I'm cracking on your children, but that's my opinion. You know what they say about opinions.
At least the 1600/1900 sucks significantly less than the 2660 I had for awhile. Ugh, what a piece.
I cannot argue with you there, but that's why I like the COM-120B - I had the time to really optimize the spec-an there, where I really wasn't given that time on the 2975.tvsjr wrote: Bah. I had the opportunity to buy a 1900 - took the 8921 instead. The buffering when using the spec-an/TG sucks on the 1600s, 1900s, and even the 2975s. It's way too long. The 8921 shows changes near-instantaneously, IFR notsomuch.
The 3900, on the other hand....
No, I had very little to do with the 1[69]00 and nothing to do with the UI.tvsjr wrote: And, the 1600/1900 UI isn't just user-unfriendly... it's user-hostile, IMO. I think you wrote that code so I'm cracking on your children, but that's my opinion. You know what they say about opinions. :baby:
Now, you insult the UI on the COM-120B or 2975 at your peril ;).
That is one of the subjects I keep harping on to the other designers: it's hard to get them to think in terms of real test situations sometimes.
COM-120 isn't bad... 2975 isn't bad either. Neither is as intuitive as the 8921 - in the case of the 2975, that's largely due to many more available options. A friend of mine has used a COM-120B for years and is fairly pleased with it.
Here's a big test: a friend, who had never used a service monitor before, recently purchased an 8921. With about 30 minutes of coaching, he was aligning radios and tuning duplexers (properly, I might add). I don't know of any other boxes that are quite as intuitive to use.
Also, the 8921's dynamic range is quite handy when tuning pass/notch duplexers.
Unfortunately, engineers are, in general, bad at UI - I exemplify this. I handle all the heavy lifting on the backend... let some artiste type do the UI. I can tell you what I like and what I don't like, but I can't build a user-friendly UI from scratch.
I think you need to send me a 3900 for long-term demo. I could get the unit some serious exposure, and make some UI suggestions too. PM me for my shipping address.
Here's a big test: a friend, who had never used a service monitor before, recently purchased an 8921. With about 30 minutes of coaching, he was aligning radios and tuning duplexers (properly, I might add). I don't know of any other boxes that are quite as intuitive to use.
Also, the 8921's dynamic range is quite handy when tuning pass/notch duplexers.
Unfortunately, engineers are, in general, bad at UI - I exemplify this. I handle all the heavy lifting on the backend... let some artiste type do the UI. I can tell you what I like and what I don't like, but I can't build a user-friendly UI from scratch.
I think you need to send me a 3900 for long-term demo. I could get the unit some serious exposure, and make some UI suggestions too. PM me for my shipping address.