Power Supply

[mike9h29]

Hello.

I need a Power Supply to power a CB, VHF, UHF and HF Radios.

I think I will need around 50/65A (12V) as I may add a linear amplifier in the future.

I can buy a PC PSU with separate rails for 12V or I can buy a big transformer and filter its output.

What do you think will be the best?

I dont need variable voltage.

Thanks

Mario

[Toasty]

Re: Power Supply

A heavy duty car battery with a very good 20-30A charger that will do float charging would probably be better. You're not going to be on continuous TX, so factor that in.

If not, then smaller, individual 10-20A power supplies to run 2 units would be best. If a "big" one were to fail, you'd lose the use of the whole setup.

What amount of amperage do the units draw individually on TX?

Toast

[mike9h29]

Re: Power Supply

A heavy duty car battery with a very good 20-30A charger that will do float charging would probably be better. You're not going to be on continuous TX, so factor that in.

If not, then smaller, individual 10-20A power supplies to run 2 units would be best. If a "big" one were to fail, you'd lose the use of the whole setup.

What amount of amperage do the units draw individually on TX?

Toast

I dont know exactly the current of the units, but I found on the internet that an HF Transceiver requires a minimum of 25A for TX.

Will a High End PC PSU do the job?

[Th3_uN1Qu3]

Re: Power Supply

One of the modern units with DC-DC VRMs for the minor rails, where you can get all power on 12v alone, will do. You'll have to do a slight modification of the feedback circuit to bump the voltage up a tad. Or if your equipment is happy with just 12v let it be, but radio equipment is generally spec'd for 13.8v.

[ipman]

Re: Power Supply

12V will prevent the transmitter to obtain full power. The power supply can be modified, if you know how to, but any switching supply will supply noise.
The best solution is one biiiig transformer, prefer a toroidal one.

[Toasty]

Re: Power Supply

Power supplies, such as Astron, are made for these types of applications. They produce the necessary 13.8v. A 25A continuous unit with 30A intermittent would cost ~$175 US.

That said, a car battery with a 300A CCA rating can be had for ~$50 and a decent 20A charger with float capability for ~$75 US.

You should change the name of this thread. There are a bunch of HAM operators in here who could give you some pointers for your setup. Click the red triangle under anyone's name and ask the moderators to change it. Something like "Help - Power Supply suggestions for VHF UHF setup"

Toast

[Jack Crow]

Re: Power Supply

Guys
On the bench I use an "Ebay" special.
It's a small switcher good for about 27 amps at 14 volts.

I do a lot of 110 watt mobile radios and have yet to slug it.
It seems to be RFI immune.

It's been on and running for over 2 years with zero issues.
Think I spent less than $60 on it.

Hard to kill.

Hope it helps.
Jack Crow
Herndon VA

[mike9h29]

Re: Power Supply

12V will prevent the transmitter to obtain full power. The power supply can be modified, if you know how to, but any switching supply will supply noise.
The best solution is one biiiig transformer, prefer a toroidal one.

Will connecting some big capacitors to the output of the psu kill the noise please?

[mike9h29]

Re: Power Supply

Ok, I liked the idea of using a car battery, but I am afraid of it as it may explode and this will be used inside a house.

I tried to find a transformer but I cant find any.

I decided to go for SMPS. But I need some help please.

How can I adjust the voltage of a 12v PSU to 13.8v please?

Will connecting Big Capacitors to the output help with noise? (I just asked this question above)

Thanks

Mario

[Toasty]

Re: Power Supply

https://cdn.badcaps-static.com/pdfs/...644350b7da.pdf

https://cdn.badcaps-static.com/pdfs/...b3145bb959.pdf

http://www.users.on.net/~endsodds/safe.htm

Try Googling:

radio bench power supply from atx

radio bench power supply computer atx

.

[Toasty]

Re: Power Supply

Guys
On the bench I use an "Ebay" special.
It's a small switcher good for about 27 amps at 14 volts.

I do a lot of 110 watt mobile radios and have yet to slug it.
It seems to be RFI immune.

It's been on and running for over 2 years with zero issues.
Think I spent less than $60 on it.

Hard to kill.

Hope it helps.
Jack Crow
Herndon VA

Any branding on that Jack? Something to narrow it down a bit on eBay?

Toast