Got it. I don't plan to use them above 7 MHz. I also got the plastic
sockets per your suggestion.
Rob
K5UJ
On Thu, Jul 15, 2010 at 6:24 PM, Carl <km1h@jeremy.mv.com> wrote:
> The 4X1 can get quite squirrely at times, especially 10-15M and over 5KV. Do
> your grid connections with copper strap to a single point ground. I wound
> the P.S. with strap also.
>
> Use a big glitch resistor at the base of the plate choke and out of sight of
> the chimney. Dont skimp on the bypass either.
>
> Carl
> KM1H
>
>
>
> Carl
> KM1H
>
>
>
> ----- Original Message ----- From: "Rob Atkinson" <ranchorobbo@gmail.com>
> To: "Carl" <km1h@jeremy.mv.com>
> Cc: "DAVE WHITE" <mausoptik@btinternet.com>; <amps@contesting.com>
> Sent: Thursday, July 15, 2010 6:45 PM
> Subject: Re: [Amps] parasitic suppressor voodoo
>
>
>> Okay! From Carl and Dave's lips to God's ears, or is it the other way
>> around. The authorities have spoken and I now proceed with
>> confidence....
>>
>> tnx
>>
>> Rob
>> K5UJ
>>
>> p.s. to the original poster--pse accept my appology for intruding on
>> the "voodoo" thread....I shall now step out of the way....
>>
>>
>> On Thu, Jul 15, 2010 at 3:00 PM, Carl <km1h@jeremy.mv.com> wrote:
>>>
>>> Agree with Dave. In the past I turned out many 1-2 holers grid or cathode
>>> driven to order; most covered 160 or 80-10M. Then I used 20-25W Globars
>>> or
>>> surplus 68 Ohm 50W Carborundums which I bought almost 100 in sealed
>>> packages
>>> for real cheap.
>>>
>>> Stopped that when all the local AM stations used the tubes until they
>>> were
>>> even almost dead as modulators or went SS. I did about 10 3CX3000A7's and
>>> a
>>> few 4CX5000A's after that.
>>>
>>> Carl
>>> KM1H
>>>
>>>
>>>
>>> ----- Original Message ----- From: "DAVE WHITE"
>>> <mausoptik@btinternet.com>
>>> To: <amps@contesting.com>; "Rob Atkinson" <ranchorobbo@gmail.com>
>>> Sent: Thursday, July 15, 2010 3:34 PM
>>> Subject: Re: [Amps] parasitic suppressor voodoo
>>>
>>>
>>> On a 2 times 4-1000A amp (5.5kv, grounded grid, cathode driven) I used
>>> two
>>> separate parasitic suppressors, each with 3 paralleled 50 ohm carbon
>>> resistors inside a 15mm diamater two-turn coil of 2mm copper wire over
>>> about
>>> 10mm length. The amp has worked flawlessly (80 thru 10m) for many years.
>>>
>>> If yours is a low band amp, you could probably make REALLY certain by
>>> increasing the number of turns on the coil. Initially with four turns the
>>> resistors smoked a little on 10m. I guessed "too much L". There was no
>>> science to building these suppressors - it was a case of looking at the
>>> W6SAI "Radio Handbook" and seeing if it worked. Voodoo? Maybe.
>>>
>>> I didn't try the amp without parasitic chokes but it seemed to work and
>>> "if
>>> it ain't broke, don't fix it"....
>>>
>>> Hope this helps
>>> Dave G0OIL
>>>
>>> --- On Thu, 15/7/10, Rob Atkinson <ranchorobbo@gmail.com> wrote:
>>>
>>> From: Rob Atkinson <ranchorobbo@gmail.com>
>>> Subject: Re: [Amps] parasitic suppressor voodoo
>>> To: amps@contesting.com
>>> Date: Thursday, 15 July, 2010, 18:40
>>>
>>> I would love to know what if any p.s. is needed on a pair 4-1000A at
>>> 4.5 KV triode connected cathode driven for 160, 75 and 40 m.
>>>
>>> rob
>>> K5UJ
>>> _______________________________________________
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>>> http://lists.contesting.com/mailman/listinfo/amps
>>> _______________________________________________
>>> Amps mailing list
>>> Amps@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>
>
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