Yaesu: FT-8800 Scanning Issue

ke6gcv

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Feb 13, 2006
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199
Location
Somewhere, Northern CA
I have a scanning issue with my FT-8800. Can anyone help?

I'm unable to receive any signal on two programmed frequencies in one of my banks. Just two! It doesn't matter if these two frequencies are split between A and B side or both on the A or B side. If I stop the scanning on either of the two frequencies, I can hear radio traffic when it's being broadcast. When scanning, I cannot.

This has only just now started to occur and is currently intermittent. Does anyone know what the issue could be?

I know it's not the programming. I haven't touched anything on it since it was last programmed it about three years ago and have been receiving broadcasts up until now.

It isn't the antenna because I was able to carry a conversation on simplex between where I live to a station up in the Tahoe area. Weak signal, of course, but we were able to converse and understand each other.

I haven't done a full reset on the radio as yet. Do you think that may help resolve the issue I'm describing?

Any recommendations? Suggestions? Please let me know your thoughts. Thank you!
 

ko6jw_2

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What are the frequencies? Check RF squelch settings. I recently had a problem hearing another station on simplex. There were bars on the display, but I couldn't hear him even with the squelch open. I checked all the setting and found the RF squelch was turned al the way up. This meant that the signal had to be over S9 to be received. It was about S5. Perfectly readable but not high enough for the RF squelch setting. This might be more critical when scanning.

In three years a lot of things can change. Coax, connectors, antennas etc. You say it is none of these things. Have you checked? The contact you made on simplex might be a different path from the other signals. You also have no benchmark for reference. Did you talk to that station three years ago? It could be a combination of factors.
 

ke6gcv

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Feb 13, 2006
Messages
199
Location
Somewhere, Northern CA
What are the frequencies? Check RF squelch settings. I recently had a problem hearing another station on simplex. There were bars on the display, but I couldn't hear him even with the squelch open. I checked all the setting and found the RF squelch was turned al the way up. This meant that the signal had to be over S9 to be received. It was about S5. Perfectly readable but not high enough for the RF squelch setting. This might be more critical when scanning.

In three years a lot of things can change. Coax, connectors, antennas etc. You say it is none of these things. Have you checked? The contact you made on simplex might be a different path from the other signals. You also have no benchmark for reference. Did you talk to that station three years ago? It could be a combination of factors.

Both frequencies are repeated and I generally have the squelch knob at mid-level. When I first noticed this happening, I did adjust the squelch settings and also set the RF SQL level to off. Still intermittent.

You're correct in that connections can weaken over time. At the time my scanning issue started, I was running a Larsen trunk lip mount attached to a Larsen NMO2/70 antenna. It was working perfectly up until the issue started. So...

I've since punched a hole in the trunk and ran the cable to the radio and ensured continuity was good. That seemed to have fixed the issue for a short period of time before starting again.

I've also tried different antennas before and after the hole punch with same results.

Could the ceramics be starting to fail?
 

ke6gcv

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Feb 13, 2006
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199
Location
Somewhere, Northern CA
@ko6jw_2 You asked about the two frequencies. Sorry... I forgot to include them in my reply to you. One is 154.4450 MHz. The other is 160.0650 MHz. Both are repeated and tone-squelched.
 

ko6jw_2

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Explain ceramics - not sure what you're referring to.

Have you checked the SWR in the ham bands? If you have access to an antenna analyzer you can check at the problem frequencies. I would expect the SWR to be higher outside 2 meters, but that should not have a drastic effect on reception vs transmitting. By the way DC continuity though useful is not relevant to RF performance. Some antenna designs will show a dead short at DC because of their design, but be perfectly fine at VHF or UHF.
 

ke6gcv

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Feb 13, 2006
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Location
Somewhere, Northern CA
Unfortunately I don't own an SWR meter. I know they're fairly cheap for one that would let me get by. That'd be a good test to see how the antennas are.

The other two frequencies that I don't have a problem with are 155.0550 MHz and 154.8000 MHz. I receive them without issue while scanning. So... what's changed?

Three of the four frequencies run the same PL tone. So... the issue isn't there as I can receive all when not scanning.

This is very perplexing to me! It worked for the longest time. Now suddenly it doesn't unless I stop the scan. Nothing has changed except moving from the trunk lip mount to the NMO mount. And, as mentioned, it stopped receiving before I changed antenna mounts.
 

ke6gcv

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Feb 13, 2006
Messages
199
Location
Somewhere, Northern CA
Are these two channels set for full TSQL (Rx tone squelch)? If so, it's possible the user has changed tones. Try using just plain vanilla analog squelch with no Rx tone.
The channels are repeated with PL tones. As mentioned, I can stop the scanning and be able to receive a signal when there is a broadcast. I just don't receive anything when the two channels are scanning.
 
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