Power supply

[KK4SYW]

I have a YAESU FT-2900R and I am currently looking for a power supply for it. I would like to also use it to power my CB radio as well if that is possible. What I need to know is how many amps does the power supply need to have as well as some recommendations on which power supply is best. Thanks.

 

[nd5y]

You need to look in the radio's manual and find out how many amps it draws when transmitting on high power (or measure it) and get a power supply that is rated for more than what the radio draws.
What power supply is best is like asking what radio is best.

 

[n5ims]

Astron is a brand that has served me well for many years. Things to look for are voltage (most are 12v, but verify since this is an important value to match to your radios), current ratings (when powering multiple radios simply add the maximum draw on each and get a supply that's large enough to handle them all), and is the current ratings continuous or peak (often they'll be listed as a 20 amp supply that will handle 12 amps continuous and 20 amps for brief periods).

For example, you want to power a scanner (500 mA), CB (6 A), and ham radio (12 A) that all are labled to run on 12 volts. Your power supply should be rated for 12 v and at least 18.5 amps (12 + 6 + .5). Assuming that you'll only transmit on one of the radios at a time (the most current draw should be during transmit) a good 12 v 20 amp supply should work fine. If you may ever transmit on both the CB and ham radios at the same time you'll need a more powerful supply since the draw will be close to the maximum peak draw.

It's often better to get a supply that will handle more amps than you need than less. That way you can handle another radio or swap one out for another that may have a larger draw without the need to spend more for another power supply.

Volts is a constant while amps is a maximum value. If you plug a radio that's looking for 9v into a 12v supply you'll probably burn out the radio. If you plug a radio that draws 6A into t supply that's rated for 5A you may burn out the supply, but if you plug it into one that's rated for 50A both radio & supply should be fine.

 

[k3cfc]

I have a YAESU FT-2900R and I am currently looking for a power supply for it. I would like to also use it to power my CB radio as well if that is possible. What I need to know is how many amps does the power supply need to have as well as some recommendations on which power supply is best. Thanks.

Astron 30 to 35 amp will do you just fine. ebay is full of them.

K3CFC

 

[KK4SYW]

Astron is a brand that has served me well for many years. Things to look for are voltage (most are 12v, but verify since this is an important value to match to your radios), current ratings (when powering multiple radios simply add the maximum draw on each and get a supply that's large enough to handle them all), and is the current ratings continuous or peak (often they'll be listed as a 20 amp supply that will handle 12 amps continuous and 20 amps for brief periods).

For example, you want to power a scanner (500 mA), CB (6 A), and ham radio (12 A) that all are labled to run on 12 volts. Your power supply should be rated for 12 v and at least 18.5 amps (12 + 6 + .5). Assuming that you'll only transmit on one of the radios at a time (the most current draw should be during transmit) a good 12 v 20 amp supply should work fine. If you may ever transmit on both the CB and ham radios at the same time you'll need a more powerful supply since the draw will be close to the maximum peak draw.

It's often better to get a supply that will handle more amps than you need than less. That way you can handle another radio or swap one out for another that may have a larger draw without the need to spend more for another power supply.

Volts is a constant while amps is a maximum value. If you plug a radio that's looking for 9v into a 12v supply you'll probably burn out the radio. If you plug a radio that draws 6A into t supply that's rated for 5A you may burn out the supply, but if you plug it into one that's rated for 50A both radio & supply should be fine.

Ok. Thank you very much. I wasn't sure if having too many amps would mess with the radios. I have heard that Astron is a very good brand and that is what I am leaning towards. Thank you again.

 

[rapidcharger]

Astron 30 to 35 amp will do you just fine. ebay is full of them.

K3CFC

Ebay may be full of them but lately they've been selling for the same price a new one in the box with warranty and return period from a reputable dealer. Especially those RS-35's.
My advice would be to see what their price is for a new one so you don't overbid.

 

[k3cfc]

My bad. i normally buy the bad ones for cheep, repair them then use or sell them.

Cheers

K3CFC

 

[LtDoc]

And to confuse things just a little more...
Power supplies always have two ratings, ICS and CCS. Those are Intermittent Current Supply and Constant Current Supply. The first one, ICS, is for 'surges', very short durations. The second, CCS, is what it will supply constantly, all day long. That ICS rating, because it's a bigger number, is the one that's used for advertising most often. It's the truth, not a 'lie' on the manufacturer's part, but you have to know what they are telling you. If that ICS rating is 10 amps and your radio typically draws 9 amps, then you are making that power supply really sweat, it ain't just loafing along. Count on that power supply getting 'tired' and falling down, you know? Find and pay attention to that CCS rating. As long as it's more than the typical draw of your radio(s) it should do just dandy.
In general, the ICS rating is always something like 10 - 40% more than the CCS rating.
- 'Doc