Hello Frank:


Frank Gilliland wrote:
On Mon, 27 Dec 2004 08:56:43 -0800, Jay in the Mojave
wrote in :


Hello Frank:

Hope you had a enjoyable Christmas.



I did, thanks. Did you have fun decorating the Joshua Tree?

Thats a big Bozo No No, we are not allowed to cut down the Joshua Tree's
and such. But some people do put lights on them. There is a commitee
that use to go around and count the darn tree's. New contruction is the
omnly way I seen them cut down and removed. I have a few tree's on my
property but there out of the way.

You might have a problem with the regulators. If more than one
alternator is used it's best to run the second from a 'slave'
regulator that's controlled by a 'master' on the first alternator. If
you don't then one alternator will pull the full load until the
voltage drops down to the regulated voltage of the second. The result
is "stepped" regulation and can be quite noisy.

Is this advice from experience?



Actually, yes.

Ok I have not heard of this noise but will keep an ear for it.



I have seen many alternators tied
together and not noticed any noise. When the load is applied to the
alternators is when they will be putting out the high currents, and
voltage regulators will be monitoring the out put of its alternator.

I know at times the alternator diodes shutting off will cause a noise,
that can be cured by a bypass capacitor on the alternators output terminal.



You probably didn't notice any noise because you were running AM and
the load drew down to the second alternator on key-up. Running SSB
would be a different story and your audio would include a 'clicking'
that followed the audio. But of course you wouldn't hear it anyway
because it happens when you are transmitting.

Anyway, stepped regulation is very hard on an alternator, causing
frequent surges through the field coil and regulator. They aren't
designed to work like that.

I have to agree with that. The 120 amp alternator I had on my put and
park mini truck feed the vehicles system and of course charged the
battery. I used a 4 pill Amp that had wild differances in current draw
from almost nothing to a full on 80 amp draw. This was noticable when
the engine was running at around 3000 RPMs going down the highway while
talking SSB. It would end up stretching the single V belt that would
only last about 4 weeks. I came to have several spares belts and made up
a tool kit that would allow a fast change of the belt, as I got good at
it from experence. As I had changed many belts, I finnialy installed the
stock 65 amp alternator from just being sick and tired of having to
change the belt.


Maybe that's why Motorola designated their cheap CB amp transistors as
MRF454 and MRF455 -- to appeal to the 'big engine' mentality.

Yeah I am sure thats possible, but the nerd linger who designates the
numbers I am sure sets behind a desk and has his car serviced by normal
people.

I would have a number like MRF-HP/454CI-Inc. hehehehehhehe

Matched transistors would go by Balanced MRF-HP/454CI-Hipo Inc
Or even PT2M454-Hipo Inc (Pettle to the Metal) OH YEAH!

Jay in the Mojave