Astron RS-50A

[Se7en]

just picked up a Astron RS-50a off Craigslist.
running a ranger 696fd1 and ts 500v swr is 1.1.0 across all fourty cb bands. 90w dead-key and swing to over 500w? why does this happen? in the mobile i see maybe 400w tops. power supply is putting out a strong 13.8v ...... 6' RG8 mini and 50' RG8 (big stuff).

 

[Robb]

On AM if you run more than 100% modulation, you will see a ratio of greater than 1:4 of carrier watts to PEP watts. With a 90 watt dead key carrier; then it should be 360 watts. That said, you might consider a 100 watt dead key carrier and turn the modulation down to achieve 400 watts PEP watts. Otherwise, the higher PEP is a result of too much modulation (greater than 100% = distortion). Such is the nature of CB radio.

As far as seeing more wattage on the PS as opposed to your ride; then I suspect that the power cables aren't sufficient or your electrical system isn't up to snuff. Apparently, your power supply is providing more current than your ride is. Just some observations . . .

 

[BOOTY MONSTER]

that's a 50 amp peak power supply . id suggest turning down the amp so it peaks 350 watts max . even at 300 watts it will be a rare day that 500 pep makes a contact that 300 pep wont .

 

[Se7en]

this best picture i could snap of the top end.
aaaaaauuuuddddiiiioooo

 

[Robb]

Keeping the 90 watt dead carrier, I would turn the modulation down until I saw about ~360 watts PEP. That is the difference between sounding 'clean' or 'raspy'. That would make it a 1:4 ratio too - BTW.

As Booty said, that is really taxing that PS. By turning down the modulation/mic gain; the power supply you save might be your own . . .

 

[Se7en]

yea i use the knob on the amp turned it down to like 300w? pep. i know my meter isnt 100% pep, but it works! anyways... im going to open up this power supply see whats inside replace the power switch. it flickers... no disco's here!

 

[AudioShockwav]

90w dead-key and swing to over 500w? why does this happen? in the mobile i see maybe 400w tops. power supply is putting out a strong 13.8v

If you open the T/S and put a good volt meter across the + and Neg in the amp I bet you are not holding 13.8 volts when you hit it hard.
You have voltage drop going on somewhere in the mobile.
The leads from the power supply i am sure are much shorter than the wires going all the way to the battery and or your return back (-) is longer as well.
Robb is 100% on that one

73
Jeff

 

[Se7en]

on the base here the power wires are 1' each. in the mobile its 8'.
all i know is i like my base now more then the mobile!

 

[AudioShockwav]

The RS 50 is 35 amps @ 100 % duty cycle (continuous )
and 50 amps @ 50 % duty cycle ( 5 min on, 5 min off )
According to Astron, but not everyone agrees with the Factory spec`s,
Don`t stress it to much..... And then go read this.

Introductory Information on Astron power supplies

there is some really good info here in the Astron Power supply's, and how to build them up.
Everyone that owes one should read this page.

73
Jeff

 

[BOOTY MONSTER]

what size alternator do you have in the vehicle ?

 

[Robb]

yea i use the knob on the amp turned it down to like 300w? pep. i know my meter isnt 100% pep, but it works! anyways... im going to open up this power supply see whats inside replace the power switch. it flickers... no disco's here!

I think what you are saying is that the meter probably isn't that accurate. You are probably right about that. But if it is relatively accurate; then I would accept the reading for 90 watts for the deadkey, and also accept it if it showed 360 watts for the PEP. Its not a Bird meter; that is for sure. If you adjust your output until you see a 1:4 ratio, that should be fine for now. At least you aren't under or over modulating it to some degree either way.

Running that supply with 360 watts PEP should mean that it is using about 35 amp draw. That should be fine for that supply. But it can be modded, as ASW said.

By the way - Have you heard - that the Bird is the word?
Humma mao mao . . .

 

[Se7en]

lol yes bird is the word. so... where is my bird????
@ booty monsters alt in mobile is 135amp.
@ audioshockwaves you would never guess what i payed for the astron .

so, i opened it up to find 5 dead moths inside (protein yum yum), a top half of plastic cigarette wrapper, some shredded paper. ( will be posting these treasures i found, In the forum swap shop)

very dusty inside. but looks neat/clean.

 

[TonyV225]

Well I dont want to start a p!$$ing match but.... Ide rather have and Ide trust radio shack 2000 watt model as he has over alot of the $h!+ thats sold other places these radio shack meters use the same curcuitry as the old yaesu meters have.

I have checked these radio shack meters against other meters I have and there spot on with the average pep readings. I have several of these meters and buy them when I see them forsale their able to run from the 180 - 10 meter band so it wide coverage.

I have a few of the analog models aswell as the digital model which I have modified all for better stablized PEP readings and movement.

 

[Se7en]

Well I dont want to start a p!$$ing match but.... Ide rather have and Ide trust radio shack 2000 watt model as he has over alot of the $h!+ thats sold other places these radio shack meters use the same curcuitry as the old yaesu meters have.

I have checked these radio shack meters against other meters I have and there spot on with the average pep readings. I have several of these meters and buy them when I see them forsale their able to run from the 180 - 10 meter band so it wide coverage.

I have a few of the analog models aswell as the digital model which I have modified all for better stablized PEP readings and movement.

well, someday ill buy a mta-20 .... tho im not to happy that they like to bounce up and down when checking wattage.:bdh:

iv had 2 of these radio shack meters and i like it. it may not be the easiest to read but your absolutely right it is better than alot of the trash that there making today 4-10

 

[AudioShockwav]

Do not get to hung up on meters, what you have is fine, hey it just did what it was supposed to do, that is showed a output difference from the base to the mobile....
It should do almost the same in the mobile as on the base.
Question:
are you taking the Watts out reading with the engine running, or off.
And for real, if you take your voltmeter, and clip the leads across the power cables inside the amp and measure the voltage while modulating the amp, what is the reading?

Oh just thought of this...is it the same radio in the car (or truck)?

73
Jeff