Mike,
Been here, done this. Have the amp sitting in the garage now.
I went legal limit HF mobile when I owned my hotshot trucking company.
Started out with a remote controlled '16 pill' Cb amplifier from
Messenger. Has remote control, fans, etc. Was a 2 into 16 amp. Removed
the two drive transistors and with 100 in, I'd see 1.5 kw or thereabouts
out. Because of the transformers being designed for '10 meters', it was
more efficient in the upper hf band. I tried a few fixes, shunt feeding
all 16 collectors and removing DC from the output transistors fixed it, as
best I could. The bias network was a total gong show, to steal VE7RF
saying. Had 1.1 volts of bias on one side, 1.5 on the other (amp is two 8
device boards combined in a clam shell config). New bias regulator
provided 10 amps of regulated bias for each 8 transistor pallet.
I ran an outboard LP filter, but with the screwdriver not sure how much of
that was necessary. Since we use our antennas on 3rd harmonics, I wasn't
going to see if I could throw a signal on 10 megs while operating 75.
Figure 20 amps draw PER TRANSISTOR! 4 transistors will peak at 80 amps
full out. My 16 would easily pull 300 amps. I ran a pair of leece Neville
alternators, and used the factory alternator for the radio and truck (truck
was an 06 Dodge Cummins Turbo Diesel). If only using ssb, a single
additional alternator and battery would have been sufficient..... But I
like AM..... So a pair of alternators, one deep cycle and one 'standard'
car battery fed the amp.
With the amplifier I had, I could easily wind up a 2.4 kw CW signal. If I
held it for seconds like that, it would start to get into electronics.
Never got a limp mode, a shutdown or anything like that, but I was
mindful. Dodge is pretty good about shielded cables as well. The dodge
was the quietest for 'diesel injector noise' I found. I bought 6
(trucks). With a 300 Watt carrier and 125 pct modulation, it worked fine
business.
And a legal limit mobile signal is about on part with a hundred Watt signal
at the house into decent antennas, textbook. I found that when going from
a hundred watts pep to fifteen times that, I had no problem making
contacts.
Was it worth it. Oh HELL yeah. Would I recommend it to someone else?
Probably not. I had the amp, batteries, alternators, etc. from a prior
life in another service. All told, I had a few thousand into the system
and countless hours. Truly, not really plug and play, especially when your
fighting a diode Junction between bed and frame due to road salt covering
the neoprene bed mounts!
Yeah, 1.5 kw finds a LOT more weak areas than .1kw!
Do not mean to discourage ya. Any questions, please feel free to ask.
Oh, bonding. EVERYTHING has to be bonded.
And chokes. Print a FEW copies of jims pamphlet. One in the bathroom,
nightstand, glove box of vehicle, desk drawer at work. Yes, it will be a
short uphill battle!
--Shane
KD6VXI
On Friday, April 14, 2017, Mike Smith VE9AA <ve9aa@nbnet.nb.ca> wrote:
> I am thinking of upgrading my mobile station from 100w to something more.
> 500-600w minimum.
>
> At one time there seemed to be more choices available to the mobile ham but
> now about the only choice seems
>
> to be the Ameritron ALS-500. At $1350 CDN + 15% tax and then shipping,
> (making it about $1600 CDN) it's not cheap for a 350-400w (CW) amp.
>
>
>
> I don't mind paying for quality, but what scares me more about this amp are
> some of the less than glowing reviews.
>
>
>
> In my limited research I've found:
>
> (RM Italy seems like lower power and some are illegal in NA)
>
> (SGC no longer making the power cube I don't think)
>
> (THP out of business)
>
>
>
> What else is out there?
>
>
>
> Thanks
>
>
>
> Mike VE9AA..VE9AA/m
>
>
>
> Mike, Coreen & Corey
>
> Keswick Ridge, NB
>
>
>
> _______________________________________________
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> http://lists.contesting.com/mailman/listinfo/amps
>
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