I agree with you Carl about this being the best protection I have
seen. As far as I know, it started with the Paragon and I believe
it is included in the Pegasus/Jupiter. Looking at my Jupiter
schematic here, I see a current sensing resistor in the power line
to the PA stage. Current information from that resistor is
conditioned and sent to the ALC circuit through a potentiometer
labelled "Set PA Current Limit". This leads me to believe that
the PJ's are equally like the Paragon, Omni V and Omni VI.
-Lee-
On 10 Mar 2002 at 22:14, Carl Moreschi wrote:
> The Omni VI and Omni V had the best protection I've ever seen
> for mismatched antennas. Instead of folding back the transmit power
> by sensing SWR, they have a collector current sensing circuit that
> adjusts drive so that the finals can never draw more than 20 amps.
> These two radios do not require a power supply that shuts off with
> excessive current.
>
> It is too bad they dropped this circuit in the Pegasus and Jupiter. I
> bet they will have it in the Orion.
>
> Carl Moreschi N4PY
> Franklinton, NC
> ----- Original Message -----
> From: "George, W5YR" <w5yr@att.net>
> To: "John Buck" <kh7t@arrl.net>
> Cc: <tentec@contesting.com>
> Sent: Sunday, March 10, 2002 8:56 PM
> Subject: Re: [TenTec] Re: Tuners
>
>
> > John, how does this relate to the high-speed circuit breakers built
> > in to TT power supplies and required if non-TT supplies are used?
> >
> > Just curious, since I read your story and then I read other postings
> > about how a low impedance load drives the collector currents to 30
> > amps almost instantly and if the fast breaker doesn't operate, poof!
> > there go the finals . . .
> >
> > Straighten me out! <:}
> >
> > 73/72/oo, George W5YR - the Yellow Rose of Texas
> > Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
> > Amateur Radio W5YR, in the 56th year and it just keeps getting
> > better! QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771
> > I-LINK 11735 Icom IC-756PRO #02121 Kachina 505 DSP #91900556 Icom
> > IC-765 #02437
> >
> > All outgoing email virus-checked by Norton Anti-Virus 2002
> >
> >
> > John Buck wrote:
> > >
> > > The TenTec design approach of designing a Crunch proof 100 watt
> > > amplifier with at least a 3 to 1 full power capability will make
> > > it easy to use many antennas over the whole band without tuner and
> > > without blowing up the radio.
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
>
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