Only use SSB with engine running !?

[SvenG]

That's the admonition in either the ICOM 802 or the AT 140 instructions, don't remember which one.

Two questions ...

I that really necessary ?

Is it only during transmission when there is a high power draw ?

In case the batteries can't meet the load, what's the damage from transmitting with a less than perfect power source ?

While a diesel (old fashioned, non-computerized) might not produce much RFI I'd think that in general you'd want as FEW systems as possible running while doing SSB monitoring. Who wants all that noise ?



-Sven

[SoonerSailor]

The M-802 should do fine on fully charged batteries without having the engine running - assuming the power wiring from battery to radio is of sufficient size. If you operate the radio at input voltages less than it wants to see (and this depends somewhat at the power level the radio is transmitting at) you will have distortion of a transmitted signal, but won't damage the rig.

The radio will receive fine with voltages much lower than required for transmitting.

Having said all that, the M-802 tolerates sub-optimal voltages better than most Ham rigs. I don't know at what input voltage (at the radio, at the end of it's supply wiring) it will start to have problems at full power operation, maybe someone else has that data.

[SvenG]

Many thanks. That's kind of what I guessed but I didn't know.

'preciate the answer.



-Sven

[Paul Elliott]

I operate my SSB with the engine OFF. The alternator and battery charging system generate too much hash for good reception. Also, the engine noise (acoustic) probably gets into my microphone, but I've never tested this.

We also have a pretty massive battery bank, so voltage sag when transmitting hasn't been an issue.

[rebel heart]

Yeah I need everything off to work my 700pro. Inverter and engine in particular.

[gjordan]

A note on SSB radios, I recently had a telephone conversation with a fellow who had twice left Mexico for the Marquesas, and had to turn around to get their auto pilot fixed. The first try took them a few days out of Mexico, and their autopilot packed up. After waiting on parts, they left again and again their autopilot packed up, but they made the connection between the first time and the next time. When they hit the MIKE button on the SSB, it blew the circuits in the autopilot. By the time it was fixed the second time, they gave up and went back up the west coast, being sure to turn the autopilot off before checking into the net. Is there a lesson here??? Maybe buy an Aries or a Fleming, or maybe there is a surge protector for autopilots that doesnt let low voltage fry them. This was told to me to be a well respected, below decks autopilot, not some tiller pilot. just think about that for a while. _____Grant.

[phorvati]

Originally Posted by gjordan

A note on SSB radios, I recently had a telephone conversation with a fellow who had twice left Mexico for the Marquesas, and had to turn around to get their auto pilot fixed. The first try took them a few days out of Mexico, and their autopilot packed up. After waiting on parts, they left again and again their autopilot packed up, but they made the connection between the first time and the next time. When they hit the MIKE button on the SSB, it blew the circuits in the autopilot. By the time it was fixed the second time, they gave up and went back up the west coast, being sure to turn the autopilot off before checking into the net. Is there a lesson here??? Maybe buy an Aries or a Fleming, or maybe there is a surge protector for autopilots that doesnt let low voltage fry them. This was told to me to be a well respected, below decks autopilot, not some tiller pilot. just think about that for a while. _____Grant.

Sounds to me their radio installation or autopilot installation had issues. Whith blown circuits, a lot of the times it is the ground or the return path. People forget that current needs a path back to the negative of the battery. Just because you route it to the engine block, or keelbolt and it seems to be working, doesnt mean the installation is done.
With engine on, and back then I had a gas engine, I had a lot of EMI on the SSB reception/transmission. Digital transmission like pactor rejects it much better then trying to talk to people. That's really the only transmissions I did.

[SV THIRD DAY]

Too bad that Icom can't make a manual as good as their Radio.