[Amps] rocky point effect, barnacle bill

[2]

>I don't know, Rich. Tom, told me on this very forum that Ameritron sized
>their glitch resistors based on service history. I have some glitch
>resistors in
>my shop that Tom recommended (I believe they are RCD brand). They
>came from Ameritron's parts stock.

Apparently, Tom is beginning to come around.  A few years back he said 
that glitch resistors were not needed due the high ESR of the filter caps 
Ameritron uses*.   Who knows? - maybe someday Tom will realize that high 
VHF-gain tubes like the 8877 need a VHF parasitic suppressor to make them 
less unstable in MF/HF applications.  It seems he's beginning to think 
better because about a month ago he got the series-to-parallel 
equivalency idea behind a VHF parasitic suppressor pretty much right - 
except for the part about how a VHF suppressor reduces VHF amplification. 
  

*  I have never seen an electrolytic with enough ESR for glitch service.  
 And if there was one made, it would run way too hot to last because heat 
is the enemy of electrolytics.
>
cheers, Mike
>
>----- Original Message -----
>From: "2" <2@vc.net>
>To: "Steve M" <wmoorejr@cox.net>; " AMPS" <amps@contesting.com>
>Sent: Saturday, August 24, 2002 3:11 PM
>Subject: Re: [Amps] rocky point effect, barnacle bill
>
>
>>
>>
>> >Rich,
>> >
>> >I had the diode on the wrong board. It is on the ps board immediately to
>the
>> >right of the big ribbon cable in the pics on this site.
>> >
>> >http://hamradiomarket.com/Articles/Ameritron%20AL-800H.htm
>> >
>> >I'm not seeing a glitch resistor in these pics. Still might be in there
>> >somewhere. ?
>>
>> **  MFJ/Ameritron's chief engineer, Mr. Tom Rauch, apparently does not
>> employ glitch resistors in Ameritron amps.  He said there's enough ESR in
>> the electrolytic capacitors to do the job.  Modern electrolytic caps do
>> not have even one-third the needed R.
>> >
>> cheers, Steve
>> >
>> >----- Original Message -----
>> >From: "2" <2@vc.net>
>> >To: "Steve M" <wmoorejr@cox.net>
>> >Sent: Saturday, August 24, 2002 5:49 AM
>> >Subject: Re: [Amps] rocky point effect, barnacle bill
>> >
>> >
>> >> A glitch resistor is in series with the HV DC supply.  It limits peak
>> >> discharge current from the filter caps - which is the apparent energy
>> >> source for gold-sputtering from the surface of the grid.  In 3-500Z
>> >> amplifiers, a glitch resistor tends to reduce bending at the
>unsupported
>> >> mid-point of the filament helix.
>> >>
>> >> >Don't know. Both the Ameritron and the National survived and ran fine
>> >with
>> >> >normal meter readings - oops, except I did have to replace a 1N 4001
>> >diode
>> >> >on the AL 800H qsk board. It had to do with grid current reading too
>> >high.
>> >> >Grid current was showing around 125ma or more until I replaced this
>> >diode.
>> >> >
>> >> Where is the diode in the circuit?  Did it short or open?
>> >>
>> >> tnx, Steve
>> >> >
>> >> >----- Original Message -----
>> >> >From: "2" <2@vc.net>
>> >> >To: "Steve M" <wmoorejr@cox.net>; " AMPS" <amps@contesting.com>
>> >> >Sent: Friday, August 23, 2002 8:50 PM
>> >> >Subject: Re: [Amps] rocky point effect, barnacle bill
>> >> >
>> >> >
>> >> >>
>> >> >>
>> >> >> >For what it is worth dept. A while back I bought a used Ameritron
>AL
>> >800H
>> >> >> >that uses a pair 3cx800. About a minute or so after I first turned
>it
>> >on
>> >> >> >[nothing hooked to it but the power cord] I heard a very loud bang.
>So
>> >I
>> >> >> >shut if off and inspected for damage. Nothing found....
>> >> >>
>> >> >> **  does the AL-800 use a glitch resistor?
>> >> >>
>> >> >> -  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
>> >> >> www.vcnet.com/measures.
>> >> >> end
>> >> >>
>> >> >> _______________________________________________
>> >> >> Amps mailing list
>> >> >> Amps@contesting.com
>> >> >> http://lists.contesting.com/mailman/listinfo/amps
>> >> >
>> >> >
>> >>
>> >>
>> >> -  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
>> >> www.vcnet.com/measures.
>> >> end
>> >>
>> >
>> >
>>
>>
>> -  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
>> www.vcnet.com/measures.
>> end
>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>
>
>
>


-  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, 
www.vcnet.com/measures.  
end