HF Rig Amperage Question

[Captain Kilowatt]

I have a reason for asking this, Captain, but was hoping I wouldn't have to give it because I know what kind of remarks are sure to follow. That said, I'll share it but ask that everyone please exercise some restraint.

The rigs I am looking at are all 100 watts. However, at my present location I will only be using it at low power because my antennas wiil be dipoles and end feds located in my attic and It is my understanding using full power in those situations is dangerous (fire hazard) and very likely to cause tvi or other electrical interference. and so, I am trying to determine what power supply I need for low power operation.

I will be limiting my transmit to 25 watts and wanted to know hat the amperage requirement would be for a radio that draws 23 amos at 100 watts, that's all. I'm guessing about 6.

Each radio will differ a little in what they draw at less than full output. Yeah you could probably get away with a 12 amp supply running at 25 watts but the price difference is very little. I still say go with a power supply that will allow full output and not worry. All it takes is to accidentally bump the power up to full output and POP!! goes the power supply and quite possible the finals in the radio as well. That itself will make the price difference between the two supplies enough to swing in favour of the heavier supply to start off with. Personally I would never run a power supply that is under-rated due to the expense if something were to accidentally happen. Also you cannot just simply say that since you will be using an indoor antenna that 100 watts will cause interference while 25 watts will not. Some cases interference will happen with 5 watts and some cases it will not happen with a kilowatt. I used to run indoor antennas when I lived in an apartment when I was first married. I ran 100 watts all the time.I had a three element wire beam on 10m and a full sized dipole on 20m and a slinky end fed. Sometimes on 80m the slinky end fed would get into the stereo in the living room and sometimes it would not. Everything else was fine regardless of the band. You can only be sure of what is going to happen by actually trying it and seeing.

 

[Riverman]

Each radio will differ a little in what they draw at less than full output. Yeah you could probably get away with a 12 amp supply running at 25 watts but the price difference is very little. I still say go with a power supply that will allow full output and not worry. All it takes is to accidentally bump the power up to full output and POP!! goes the power supply and quite possible the finals in the radio as well. That itself will make the price difference between the two supplies enough to swing in favour of the heavier supply to start off with. Personally I would never run a power supply that is under-rated due to the expense if something were to accidentally happen. Also you cannot just simply say that since you will be using an indoor antenna that 100 watts will cause interference while 25 watts will not. Some cases interference will happen with 5 watts and some cases it will not happen with a kilowatt. I used to run indoor antennas when I lived in an apartment when I was first married. I ran 100 watts all the time.I had a three element wire beam on 10m and a full sized dipole on 20m and a slinky end fed. Sometimes on 80m the slinky end fed would get into the stereo in the living room and sometimes it would not. Everything else was fine regardless of the band. You can only be sure of what is going to happen by actually trying it and seeing.

Thank you, sir.
Will be following your advice.

 

[Locutis 59]

My ham transceiver put out
50 watts and draws 30 amp
and I transmit for 5
minutes then receive for
10 minutes (and repeat).
So how many hours
on Portable Power Station.

 

[AudioShockwav]

My ham transceiver put out
50 watts and draws 30 amp
and I transmit for 5
minutes then receive for
10 minutes (and repeat).
So how many hours
on Portable Power Station.

What Portable Power Station?
Capacity?
AH rating?
I use a Yeti goal zero 1500x to run a 897d and a autotuner. Depending on the amount of TX time it will vari. On Receive it draws less than 1 amp and can last for days. TX pulls about 20.5 amps on Ten meters FM full power@100 watts, brick on the key.
In that condition 100% duty cycle approx 10-15 hours depending on the state of charge. Solar panels help that depending on sunlight available.
In SSB mode maybe 12-14 amps AVG approx 20-22 hours intermittent use.
YMMV depending on size of unit, state of charge ect.


73
Jeff