Sounds like you have everything well in hand, Kevin.
Looks to me like someone drove it too hard on 10 meters.
Good luck,
Phil, K5PC
Phil Clements
410 VZ CR 4903
Ben Wheeler, TX 75754
----- Original Message -----
From: Kevin P <kpevin@mediaone.net>
To: Phil Clements <philk5pc@tyler.net>
Sent: Tuesday, April 18, 2000 11:18 AM
Subject: Re: [AMPS] L4B parasitic reistors
> Hi Phil,
>
> All three resistors are inside the coil. According to the schematic and the
> color code on the resistor it is 15ohm 5% (brown, green, black, gold). I
> really have no idea what the previous owner was doing with this amp, all I
> can say it looks like new and the tubes are full output and appear to be
> original (1974 date code). I also noticed one of the two 1000pf 5kv
> doorknob coupling caps looks blistered - even the metal threaded ends look
> bumpy. Drake has them for 3.00 each so I'll get a few of those to keep
> around.
>
> 73,
> Kevin
>
> ----- Original Message -----
> From: "Phil Clements" <philk5pc@tyler.net>
> To: "Kevin P" <kpevin@mediaone.net>; <amps@contesting.com>
> Sent: Tuesday, April 18, 2000 10:01 AM
> Subject: Re: [AMPS] L4B parasitic reistors
>
>
> > Subject: [AMPS] L4B parasitic reistors
> >
> >
> > Hi All,
> >
> > I picked up a very nice L4B the other day that works FB (only used it on
> 40/80m
> > though). When I took it apart to clean the tubes and dust off the chassis
> I
> > noticed that two of the three 15ohm 2watt resistors on the each suppressor
> was
> > completely burned through in half. Interstingly, one resistor out of the
> three
> > on each one looks like it never got hot at all. I am going to replace all
> the
> > resisters but I was wondering why two out of the three resistors are
> almost
> > vaporized while one is intact. I dont see any sighs of arcing or
> overheating
> > anywhere else in the amp - it looks like brand new otherwise.
> >
> > 73,
> > Kevin
> > KB9UPV
> >
> > 15 ohms seems a bit low to me, Kevin. I'll bet they are supposed to be 150
> ohms
> > each, to give 50 ohms total. This is the common design for 3-500Z
> suppressors.
> >
> > I'm not familiar with the L-4B, do all three resistors reside outside the
> coil,
> > or
> > one in and two out, or all three inside?
> >
> > (((73)))
> > Phil, K5PC
> >
> >
> >
> >
> >
> >
> >
>
>
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