Got it and thanks for all the help!!
I found the problem with the tube.
right under the tube cap there is a wire coming down and routing around the
filaments. on the top (inside) the tube there are two small "springs" for lack
of a better term. On the good tubes (all 3) these two springs are sitting down
on the tube structure inside the tube missing the wire from the tube cap by at
least 1/8 inch or more. On the "bad" tube one of these springs is out of
postion poped up and actually touching the cap's wire..
anyway have new tubes on roder thanks for the help..
*********** REPLY SEPARATOR ***********
On 01/03/2005 at 12:26 PM Charlie wrote:
>Sounds like good troubleshooting technique to me. Maybe you can evaluate
>the
>tube further to isolate what is wrong with it.
>
>Charlie
>Ham Radio - AD5TH
>www.ad5th.com
>Live Blues Music
>www.492acousticblues.com
>
>
>
>
>----- Original Message -----
>From: "Dan" <dpipes@earthlink.net>
>To: <Amps@contesting.com>
>Sent: Monday, January 03, 2005 11:05 AM
>Subject: Re[2]: [Amps] ok ONE more time <g> Ameritron 811H
>
>
>well thanks to everyone's help I think I have it fixed.. well not fixed
>but
>at least found the problem. I replaced the 51 ohm resistor a second time.
>this time at the advice of a local buddy he said pull that tube that that
>resistor is tied to and try again. well pull the tube turned the amp on
>and
>all powers up without the excieing bang/pop.. and flash <g>
>
>I did not try to load withonly 3 tubes but seems that proves the problem
>is
>with the tube.. I have ordered a set as stated earlier and will have 3
>extras i guess ..
>any comments about this "test"..
>
>thanks
>
>*********** REPLY SEPARATOR ***********
>
>On 01/03/2005 at 7:36 AM carl seyersdahl wrote:
>
>>The grid resistors are shown in my 811H manual as R 19 thru R22.they are
>>listed as 51 ohms, 2 watt metal oxide.
>> I have always replaced these with 33 ohms 1/2 watt , and I've never had
>>any problems, but then I've always replaced the parasitic suppressors with
>>Mr. Measure's
>> Nichrome (not microbe) types. Never had any more trouble that I know
>>of.!!!!!
>> carl / kz5ca
>>----- Original Message -----
>>From: "Dan" <dpipes@earthlink.net>
>>To: <Amps@contesting.com>
>>Sent: Sunday, January 02, 2005 6:16 PM
>>Subject: [Amps] ok ONE more time <g> Ameritron 811H
>>
>>
>>You guys have had the answer everytime so far. I bought a 2nd hand
>>Ameritron
>>811H amp. It has worked very well exept .. at first start up serveral
>weeks
>>ago.. after it had been stored when i first turned it on it arec at the
>>vents 9right side) switched it off.. long story short after a few turn ons
>>and off it work great.. I get good ooutpit and great reports. Well over
>the
>>past few weeks once in a while (only when I turn it on) I woud get an arc
>>same place. after it has been on and after serveral times on and off
>during
>>the day it would be fine great output and no arc even when switched back
>on
>>.. seemed like only would do it after it had been off all night and then
>>only sometimes.. I have remoed and check for any signs of arc etc never
>>found anythign..
>>Well until today.. I switched it on.. and again a little arc that was
>>visable at the vents.. and quickly this time a loud pop.
>>
>>Well obviously not a good thing. I remove the cover again and this time
>>found that one of the 53 ohm 2 watt resistors had actuall blew apart.
>onone
>>end. I shoudl mention that this time I had very little power out after the
>>arc/bang..
>>
>>In reviewing the circuit I can ot tell what these four resistors are but I
>>assume it has to do with some type of bleeder circuit to grd as all four
>>have one log to grd the other to a small wire maybe 18 ga. (light wires..
>>one is yellow one is blue and the other two are red..
>>the yellow one is the one that blew the resistor...
>>
>>The diagram they provide in the book and the parts list has to be
>>incomplete
>>as the 53 ohn resitors are nto even liosted. there are two physically near
>>the rear of the tube cage (just to the rear to the torrid) the other two
>>are
>>near the front edge of the same are... the yellow wired resistor that blew
>>is one of the two at the rear side of the tube cage..
>>
>>Any ideas? Are these bleeder circuits ? part of the neutralization
>circuit?
>>.. Any ideas what might of caused this .. this amp sat for about 3 yrs in
>a
>>closet not used.. before I got it..
>>any ideas woud be of help. Could a tube of caused it? what else shoudl I
>>check thanks
>>
>>_______________________________________________
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>>http://lists.contesting.com/mailman/listinfo/amps
>
>
>
>
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