Battery eliminater

[K7PWJ]

Has anyone found a suitable battery eliminater for the Astro Saber III? I ordered two eliminaters from Export Power on Amazon they arrived promptly. The problem with them is that they will not support the radio in the xmit mode on full power. Receive mode is ok and with the power set to low it seems ok. I called the company and they sent out two new ones but I had the same results. I've tried all four eliminaters on two different radios, no change.

[Bill_G]

Perhaps your power source is too soft.

[jackhackett]

Is that the one with the cigarette light plug? If so I'm wondering how much power that thing is good for, it looks like the voltage regulator is built into the cig. lighter adapter.
I was trying to see how much current an Astro Saber needs, as far as I can find it's going to be 3A or more on high power TX, depending on the model.
Can you tell us specifically which model radio you have, and do you have any specs on the battery eliminator?

[K7PWJ]

My radios are VHF Astro Saber III. I've tried powering the radio with the eliminater attached in all my vehicles and also powered it on the bench with a 30amp supply. When you key down on full power the radio shuts down. I haven't had problems with either radio when using my 1200 or 1800mah batteries. I can't find any specs on the eliminater. When I talked to the guy at Expert Power he didn't know much about the product.

[jackhackett]

Okay, the VHF's have the highest power draw, I was thinking that's what you had.

If the eliminator is the type you connect in a vehicle or to a 12V supply it's not going to make any difference if it's 30A or 300A, the eliminator has a voltage regulator to drop the voltage to the 7.5V the radio needs. This is what needs to be able to supply the proper current. If it's a cheaply made unit they may only have a 1 or 2 amp regulator in it.

Also, the mAh rating of the batteries is not the same as the maximum current they can supply, it is a rating of current available over time. So the 1200mAh battery can supply the 3A or so needed to run the radio, but for a shorter time than an 1800mAh. Higher mAh rating gives more operating time, not higher maximum current draw.

[K7PWJ]

Jack. I realize all that. I was also responding to Bill G's response about soft power. I did find specs that says the eliminater is rated at 3.0 amps out. I don't believe it.

[jackhackett]

I never know how much people on here know, so I try to give as complete an answer as I can.

In this post Gopher says he measured his at 3.2A on TX.

http://batboard.batlabs.com/viewtopic.php?t=99097

So if that's rated at 3A it might be just on the borderline, or they may have just exaggerated on the specs.

[Bill_G]

Sounds like you know what you're doing, and this batt eliminator just can't keep up with the load at high power. If possible, check the current draw to see how close you get to 3A with the radio into a dummy load, and then into it's antenna. Maybe your radio is running a bit hot into the antenna. Maybe RF is getting back into the reg and shutting it down.