troubleshoot icom 802

[captianjuan]

Hi all. I inherited an icom 802 with my boat. I have no radio experience but lots of electical and some electronic experience. When i arrived antenna was not hooked up. i ran a gto-15 wire up the and inside teh mizzen and connected it to the aft lower stay of my mizzen mast using a wire clamp. There are radar and gps wires also in the mast but they are in a different conduit. I attached the ground to two copper foil pieces and then to a bronze thru-hull.
I have a lot of noise on all channels. i tried unplugging the shore power and turning off the inverter. The only channels i can hear at all are some AM channels but i could get them with a car without an antenna.
Are the grounding and the tuner important for reception?
Are there good channels i can use to test reception?
I should add that im in honolulu so there isnt a lot going on and i think lots of funky noise from all the govt coms around here. any advice would be appreciated.

[sv_pelagia]

If you are in a marina, there will be LOTS of noise... not related to how good/poor your radio is setup.

[Bellinghamster]

Asking what might be obvious... but is your mizzen aft lower stay insulated from the mast and other rigging/bonding? If not, then you're effectively grounding your antenna lead (or if your entire rig is insulated from radio ground, connecting a very odd shaped antenna in a very unusual way!)

Hopefully you haven't tried to transmit with a shorted (or open) antenna lead - that can burn out the final amplifier stage of the radio. GTO15 is not shielded (i.e. COAX), so is effectively an antenna - RF energy will couple to nearby wires, most certainly interfering with and potentially burning out other equipment (your radar and GPS, although they are hopefully shielded cables)

You don't mention an antenna tuner (ICOM AT140 or similar) - one will be needed to match the impedance of a "long wire" antenna to the radio frequency being used.

Running the GTO15 lead for the antenna inside the mast is not the right way to do it. You'll have all kinds of uncontrolled capacitive coupling between the lead and the mast, absorbing most of the RF energy.

The typical setup is to use an insulated backstay (insulated using suitable load-rated stay insulators made for the purpose at the top and near bottom of the backstay) or easier/cheaper is to run a separate wire from near deck to masthead, insulated on both ends (google "ham radio antenna insulators"). I used polyester cord to tension the wire and provide some distance between the antenna and mast / solar arch) to reduce unwanted coupling.

The typical setup on a boat is: Radio connected to tuner via coax. Tuner located near base of antenna wire (above or below deck), tuner ground connected to ground plane. Antenna output of tuner connected to base end of long wire (antenna insulated at both ends).

There is a ton of information here and on the net about setting up SSB radios - https://www.cruisersforum.com/forums...th-133336.html for example.

Do a bunch or reading and be sure you get your Ship Station radio license and/or Amateur Radio Operator (i.e. HAM) license for your country BEFORE transmitting.

Pete
KE7CDS

[Jammer]

Originally Posted by captianjuan

i ran a gto-15 wire up the and inside teh mizzen and connected it to the aft lower stay of my mizzen mast using a wire clamp.

If you run it inside the mast it will be capacitively coupled to the mast. and behave badly particularly for transmit.

I have a lot of noise on all channels. i tried unplugging the shore power and turning off the inverter. The only channels i can hear at all are some AM channels but i could get them with a car without an antenna.

Successful HF begins with a low-noise receive environment.


Sailboats using HF while under way achieve this by being far away from noise sources and by powering down all/most local noise sources while using HF. Substantially all modern electronic devices are noise sources.


Typically it is not possible to use this approach in a harbor or even in a crowded anchorage. You have to get away from noise sources. How far? A mile or more to be sure while you're getting your setup straightened out and then you'll be able to measure the noise floor and choose a (usually shorter) distance.

Are the grounding and the tuner important for reception?

Usually not on a boat. On shore it matters more because typically a shore installation uses an antenna that is some distance away from the transceiver to reduce the amount of noise picked up from equipment in the radio room. Proper transmission line design, tuner placement, grounding, etc., helps make sure that the receiver picks up the signal at the antenna and not the nearby noise.

Are there good channels i can use to test reception?

You should be able to receive WWVH on 2.5, 5, 10, and 15 MHz with little effort. These are broadcast from a 5,000 watt transmitter in Hawaii and should be trivially easy to receive. To confirm that you have a good installation you also will have to seek out more faint signals.

[captianjuan]

Originally Posted by Bellinghamster

Asking what might be obvious... but is your mizzen aft lower stay insulated from the mast and other rigging/bonding? If not, then you're effectively grounding your antenna lead (or if your entire rig is insulated from radio ground, connecting a very odd shaped antenna in a very unusual way!)

Hopefully you haven't tried to transmit with a shorted (or open) antenna lead - that can burn out the final amplifier stage of the radio. GTO15 is not shielded (i.e. COAX), so is effectively an antenna - RF energy will couple to nearby wires, most certainly interfering with and potentially burning out other equipment (your radar and GPS, although they are hopefully shielded cables)

You don't mention an antenna tuner (ICOM AT140 or similar) - one will be needed to match the impedance of a "long wire" antenna to the radio frequency being used.

Running the GTO15 lead for the antenna inside the mast is not the right way to do it. You'll have all kinds of uncontrolled capacitive coupling between the lead and the mast, absorbing most of the RF energy.

The typical setup is to use an insulated backstay (insulated using suitable load-rated stay insulators made for the purpose at the top and near bottom of the backstay) or easier/cheaper is to run a separate wire from near deck to masthead, insulated on both ends (google "ham radio antenna insulators"). I used polyester cord to tension the wire and provide some distance between the antenna and mast / solar arch) to reduce unwanted coupling.

The typical setup on a boat is: Radio connected to tuner via coax. Tuner located near base of antenna wire (above or below deck), tuner ground connected to ground plane. Antenna output of tuner connected to base end of long wire (antenna insulated at both ends).

There is a ton of information here and on the net about setting up SSB radios - https://www.cruisersforum.com/forums...th-133336.html for example.

Do a bunch or reading and be sure you get your Ship Station radio license and/or Amateur Radio Operator (i.e. HAM) license for your country BEFORE transmitting.

Pete
KE7CDS

Thanks for the info. I do have the at140, actually i wanted ask about that as well, is there a way to troubleshoot that? also, is the tuner only important for transmission?
I should have stated that i have a wooden mast, so that shouldnt cause too much issue, but i am now concerned about having the antenna wire running next to my radar wires. hmm.
The stay is insulated. I ran up the mast, out a hole under the spreader and down about 10" to clamp on the spreader just below the insulator. there is another insulator about 4 feed up the spreader. The only other option is to run it outside the boat and up the spreaded above the insulator. That would be much more unsightly, but i am concerned with performance more than aesthetics.

[captianjuan]

Awesome. ll check out the WWVH today. thanks for the info. , so when you say they transmit on 2.5MHz or 5MHz does that mean i wound tune to 2.500.0 or 5.000.0? Ive found the internet to be surprisingly dry of information for the beginner. im just looking to test it out and have some fun as i dial it in. can you recommend a west coast or south pacific station i could try to catch here?
I should have mentioned, I have a wooden mast, so that should help with the capacitive action? I have insulators on the stay. Would you still recommend not running it up the mast and instead just go up the stay past the lower insulator?
Oh one more thing, my GTO-15 wire was a little short so i had solder in a new splice to make it to the tuner, could that cause problems?
thanks again.


QUOTE=Jammer;3893400]If you run it inside the mast it will be capacitively coupled to the mast. and behave badly particularly for transmit.





Successful HF begins with a low-noise receive environment.


Sailboats using HF while under way achieve this by being far away from noise sources and by powering down all/most local noise sources while using HF. Substantially all modern electronic devices are noise sources.


Typically it is not possible to use this approach in a harbor or even in a crowded anchorage. You have to get away from noise sources. How far? A mile or more to be sure while you're getting your setup straightened out and then you'll be able to measure the noise floor and choose a (usually shorter) distance.





Usually not on a boat. On shore it matters more because typically a shore installation uses an antenna that is some distance away from the transceiver to reduce the amount of noise picked up from equipment in the radio room. Proper transmission line design, tuner placement, grounding, etc., helps make sure that the receiver picks up the signal at the antenna and not the nearby noise.





You should be able to receive WWVH on 2.5, 5, 10, and 15 MHz with little effort. These are broadcast from a 5,000 watt transmitter in Hawaii and should be trivially easy to receive. To confirm that you have a good installation you also will have to seek out more faint signals.[/QUOTE]

[smac999]

Why is the ant cable in the mast?

Generally the at tuner would be in the laz. With a short 5’. Gto cable to the bottom of the aft stay. Which needs to be over 50’ long or so for a good ant. Isolated at both ends.

[Jammer]

Originally Posted by captianjuan

Awesome. ll check out the WWVH today. thanks for the info. , so when you say they transmit on 2.5MHz or 5MHz does that mean i wound tune to 2.500.0 or 5.000.0?

WWVH transmits from several different sites in Hawaii simultaneously. You can try all of them and should be able to receive them all.

Ive found the internet to be surprisingly dry of information for the beginner. im just looking to test it out and have some fun as i dial it in. can you recommend a west coast or south pacific station i could try to catch here?

https://www.noonsite.com/report/paci...of-radio-nets/

https://ham.aditl.com/ham-radio/pacific-hf-nets/

Keep in mind that nets come and go and that there has been a steady decline in interest over the last 10 years as satellite services have improved and come down in price.

I should have mentioned, I have a wooden mast, so that should help with the capacitive action? I have insulators on the stay. Would you still recommend not running it up the mast and instead just go up the stay past the lower insulator?
Oh one more thing, my GTO-15 wire was a little short so i had solder in a new splice to make it to the tuner, could that cause problems?

With a wood mast you are fine with what you're doing. Sorry, I assumed aluminum or carbon. The splice will be fine, ideally you would put a couple layers of heat shrink on it but that's probably not necessary. Electrically, the GTO-15 will form part of the antenna.

[SVNomadicHam]

Aloha CaptianJuan,

I am in Honolulu and have experience with SSB/RF/Antennas, etc. and have equipment that might be able to help troubleshoot your issue. Maybe we can trade some of your sailing knowledge my RF knowledge. Hit me up.

Mahalo,
Billy