Testing an M802 at home

[SausalitoDave]

Perhaps someone can offer some advice. I got a new M802 and decided to set it up at home prior to installing it on my boat. I strung a 40' horizontal wire (properly insulated) between two trees, laid a similar wire as a counterpose, and used a commercially made-up coax (50 ohm). Yesterday it worked fine, talked to a neighbor on 3.7XX Mhz. Today it is nothing but noise; I can barely make out WWV. Any volume above 10% is impossible. I live on 1 acre so there are not other homes in the area and I have turned off everything within 50 feet. No difference. Any suggestions on trouble shooting? Tried ND without effect and checked all connections - no change. I plan to try at night.

Thanks for any suggestions.

Dave
Sausalito, CA

[Jd1]

Propagation varies with lots of conditions. As you have already guessed, try at different times (what time was it when the first transmission was achieved)

[model 10]

That's just like it is on a boat, go figure. On the boat you can hear the antenna tuner relays when you switch freqs so you know it's all working. Sometimes there is nobody out there and sometimes nothing works.

[transmitterdan]

For WWV try different frequencies. It is on 2500, 5000, 10000, 15000 kHz. Usually one of those is stronger. It depends on the time of day and also time of year.

You will find similar propagation variations by frequency and time when at sea.

[SausalitoDave]

Thanks for the suggestions. I hooked up a battery (with a parallel digital volt meter) and tried again at 5:00 am - after turning off the main breaker to the house. No change. Works fine on AM broadcast frequencies; however, on all marine and Ham frequencies, nothing but noise (random, not what you would normally expect). The radio worked fine out of the box and then, without any changes, went south the next day. I may bring it over to a friends home and see if it works there; however, I think it is "broken". Ideas?

Thanks in advance.

Dave

[Xpress]

Maybe a dumb question, but are you well earthed?

[PommyDave]

The 80m band (3.5 to 4.0 MHz) is usually too noisy during the day to be much use. It comes into its own at night... so time of day is important.

[Alchemist 66]

I would take it to a local ham radio club. They usually have power supplies and plenty of antennas set up and even dummy loads to test all sorts of radios. Most are full of extremely helpful members, always willing to help.

I mention dummy load, because I don't think it's legal to transmit on marine frequencies unless you're on an FCC licensed boat in the water.

However, if they can set your radio to ham frequencies, they can transmit on one antenna and receive on another antenna.

[Scott Berg]

I'm assuming he's a licensed ham as he was saying he was working 80 meters... he didn't say he was but ....

[ka4wja]

Dave,
1) My very first thought is:
Have you accidently shut off the AGC??
(please press "F" and then "5", to check....turn it on and leave it on...)
With the AGC off, the rigs S-meter does not show any signal strengths (just like all other HF rigs, as their receiver S-meters show receiver AGC voltage)...

So, if you've somehow switched the AGC off, you'd have a lot of "volume" and what sounds like a lot of "static" ('cause the receiver gain is wide open), but unless you happen upon a strong signal from someone, you might think the radio is "broke"...

{BTW, many commercial HF radios, still to this day, have AGC "on/off" functions, but 99.999% of the time, it is best to leave it "ON"...}




2) Secondly....
Since you made contact with someone on 3.7XX MHz (in the "Advanced" or "Extra" class allocation), you obviously have the proper license, and are aware of HF radiowave propagation...
So, I assume the gist of your question is:
"What happened to my radio?"

The answers could be "anything", or "nothing"...or anything in between them!
Sorry, not trying to make light of things, just saying that there is a lot that we don't know...
--- Like, is the AGC "on"??

--- Assume you are not using the AT-140 tuner at home, but just this "40' wire" fed directly with coax?
(If you set-up the AT-140, things will be a lot easier...)

--- Assume you are in Sausalito??
If so, you can easily use NMC (USCG HF communications station in Pt. Reyes) as a test of how well your M-802 is receiving...
USCG HF Voice
You should have excellent signals from 4426 and/or 8764....depending on time of day...
What have your results been from that?

--- Have you checked out other ham bands??
And, what your results from those been??

--- Have you listened to WLO / KLB weather and traffic lists??
HF SSB Radiotelephone, Telex and Email Frequencies and Channels
What have those results been??

--- Have you listened to some local AM broadcast stations?
What have those results been??
EDIT...
Just saw your other post, where you mention that it is working fine on AM Braodcast band...
That tells me two possible things...
1- Your AGC is off....Turn it on and leave it on...
OR...
2- possible output filter issue....(do the test I described below, where you change thru the channels with the volume turned all the way down, so you can hear the M-802 Main unit "click" as it goes from 4mhz, to 6mhz, to 8mhz, to 12mhz, etc. etc. etc...if it IS doing this okay, then your trouble is most likely #1, AGC is off...or the radio has some other odd problem...which would be truly odd as these are incredibly reliable radios!)




--- Have you tried transmitting on other bands/freqs??
What have those results been??

Originally Posted by SausalitoDave

Perhaps someone can offer some advice. I got a new M802 and decided to set it up at home prior to installing it on my boat. I strung a 40' horizontal wire (properly insulated) between two trees, laid a similar wire as a counterpose, and used a commercially made-up coax (50 ohm). Yesterday it worked fine, talked to a neighbor on 3.7XX Mhz. Today it is nothing but noise; I can barely make out WWV. Any volume above 10% is impossible. I live on 1 acre so there are not other homes in the area and I have turned off everything within 50 feet. No difference. Any suggestions on trouble shooting? Tried ND without effect and checked all connections - no change. I plan to try at night.

Thanks for any suggestions.

Dave
Sausalito, CA

Have you watched the Icom M-802 Instruction Videos??
https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr


The lists of what could be wrong is long....but unlikely...
It is more likely:
a) the AGC is off....turn it on and leave it on...
b) you're not using the proper freq/band for the time of day and expected communications distance...
c) your antenna is somehow no longer connected / shorted-out...


If you turn the channel knob and go thru the channels, from 4mhz, to 6mhz, to 8mhz, to 12mhz, etc. with the volume turned all the way down, you should hear the M-802's main unit "click" as it goes from one band to the next....this is the radio switching in the appropriate output filters...

If you leave the AGC "on", and the NB "off", you should have approx.
1 to 2 bars of normal atmospheric band noise (both natural and man-made) on the lower bands (8mhz and below)....sometimes / somplaces it is quiet and you'll have no bars at all...but usually one bar illuminated on 8mhz (and/or the 40m ham band) is typical...and 1 to 3 bars is possible on 4mhz (and/or the 80m ham band)....and at night much higher noise levels from distance T-storms, etc. is almost always the case!

On the higher bands, such as 12mhz and the 20m ham band, you should not see any bars of signal illuminated from normal band noise....sometimes you can get 1 bar on geomagnetic nosiey days, but that is rare!

If you're seeing noise levels higher than what I write here, then you are receiving RFI from somewhere....
Could be powerlines, could be Wi-Fi routers, could be plasma TV's....could be anything...
(have a look at the videos I referenced above....especially #4, #5, and #9...as you'll see examples of noise, on different freqs, as well as various propagation on different freqs....



Dave, there is a whole lot more...
But, until I know more about your set-up, and how your M-802 is configured, the above is the best I can do...

Please keep us informed..
Fair winds..

John

[ka4wja]

Dave,
It's been almost 2 weeks since I gave you quite detailed and specific info/advice about your radio troubles, but we haven't heard anything back from you???

I'm wondering what you found??

Was it just the AGC was of??
Are you in Sausalito??
What is your noise level??
Have you watched the Icom M-802 Instruction Videos??

What were your results of all the other testing I recommended??

Originally Posted by ka4wja

Dave,
1) My very first thought is:
Have you accidently shut off the AGC??
(please press "F" and then "5", to check....turn it on and leave it on...)
With the AGC off, the rigs S-meter does not show any signal strengths (just like all other HF rigs, as their receiver S-meters show receiver AGC voltage)...

So, if you've somehow switched the AGC off, you'd have a lot of "volume" and what sounds like a lot of "static" ('cause the receiver gain is wide open), but unless you happen upon a strong signal from someone, you might think the radio is "broke"...

{BTW, many commercial HF radios, still to this day, have AGC "on/off" functions, but 99.999% of the time, it is best to leave it "ON"...}




2) Secondly....
Since you made contact with someone on 3.7XX MHz (in the "Advanced" or "Extra" class allocation), you obviously have the proper license, and are aware of HF radiowave propagation...
So, I assume the gist of your question is:
"What happened to my radio?"

The answers could be "anything", or "nothing"...or anything in between them!
Sorry, not trying to make light of things, just saying that there is a lot that we don't know...
--- Like, is the AGC "on"??

--- Assume you are not using the AT-140 tuner at home, but just this "40' wire" fed directly with coax?
(If you set-up the AT-140, things will be a lot easier...)

--- Assume you are in Sausalito??
If so, you can easily use NMC (USCG HF communications station in Pt. Reyes) as a test of how well your M-802 is receiving...
USCG HF Voice
You should have excellent signals from 4426 and/or 8764....depending on time of day...
What have your results been from that?

--- Have you checked out other ham bands??
And, what your results from those been??

--- Have you listened to WLO / KLB weather and traffic lists??
HF SSB Radiotelephone, Telex and Email Frequencies and Channels
What have those results been??

--- Have you listened to some local AM broadcast stations?
What have those results been??
EDIT...
Just saw your other post, where you mention that it is working fine on AM Braodcast band...
That tells me two possible things...
1- Your AGC is off....Turn it on and leave it on...
OR...
2- possible output filter issue....(do the test I described below, where you change thru the channels with the volume turned all the way down, so you can hear the M-802 Main unit "click" as it goes from 4mhz, to 6mhz, to 8mhz, to 12mhz, etc. etc. etc...if it IS doing this okay, then your trouble is most likely #1, AGC is off...or the radio has some other odd problem...which would be truly odd as these are incredibly reliable radios!)




--- Have you tried transmitting on other bands/freqs??
What have those results been??



Have you watched the Icom M-802 Instruction Videos??
https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr


The lists of what could be wrong is long....but unlikely...
It is more likely:
a) the AGC is off....turn it on and leave it on...
b) you're not using the proper freq/band for the time of day and expected communications distance...
c) your antenna is somehow no longer connected / shorted-out...


If you turn the channel knob and go thru the channels, from 4mhz, to 6mhz, to 8mhz, to 12mhz, etc. with the volume turned all the way down, you should hear the M-802's main unit "click" as it goes from one band to the next....this is the radio switching in the appropriate output filters...

If you leave the AGC "on", and the NB "off", you should have approx.
1 to 2 bars of normal atmospheric band noise (both natural and man-made) on the lower bands (8mhz and below)....sometimes / somplaces it is quiet and you'll have no bars at all...but usually one bar illuminated on 8mhz (and/or the 40m ham band) is typical...and 1 to 3 bars is possible on 4mhz (and/or the 80m ham band)....and at night much higher noise levels from distance T-storms, etc. is almost always the case!

On the higher bands, such as 12mhz and the 20m ham band, you should not see any bars of signal illuminated from normal band noise....sometimes you can get 1 bar on geomagnetic nosiey days, but that is rare!

If you're seeing noise levels higher than what I write here, then you are receiving RFI from somewhere....
Could be powerlines, could be Wi-Fi routers, could be plasma TV's....could be anything...
(have a look at the videos I referenced above....especially #4, #5, and #9...as you'll see examples of noise, on different freqs, as well as various propagation on different freqs....



Dave, there is a whole lot more...
But, until I know more about your set-up, and how your M-802 is configured, the above is the best I can do...

Please keep us informed..
Fair winds..

John

Please let us all know, as this adds to the collective knowledge!

Fair winds..

John