> Date: Thu, 15 Jul 2010 17:45:32 -0500
>> From: Rob Atkinson <ranchorobbo@gmail.com>
>> Subject: Re: [Amps] parasitic suppressor voodoo
>
>> 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.
>
> ## whoa. The fellow from G land is using THREE 50 ohm resistor's in
> parallel = 16.67 ohms.
> KM1H is using a 68 ohm -50 w globar. Carl, are did u use a SINGLE 68
> ohm resistor ??
** Yes, a single 50W Carborundum. The Globars were 50 Ohm.
> ## On my single and 2 x hole 4-1000's from the 70's.. each suppressor
> consisted
> of 5 x 250 ohm resistor's in parallel [ 2 watt carbons]
>
> ## If I remember correctly, any combo that totaled aprx 50 ohms worked
> good.
>
> ## Later on, I tried using a SINGLE 20-25 watt, 50 ohm globar, and
> that worked good too.
>
> ## whether 2 watt resistor's or globars used, in all cases, cu strap was
> used , [ 2- 2.5 turns]
> ## They were all 80-10m amps... no 160m. Back then, we were still only
> allowed 25 w on 160m, and
> loran stations were super loud. Forget when the loran was shut down.
> While the loran was still on,
> 160m was just a mess of 30-40 over S-9 crud.
>
>
>>> 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.
>
> ### watch out. Some folks on here will read you the riot act.. abt
> 'ethics' , the 1.5 kw
> limit, and other nonsense.
** That was all 20+ years ago before the Internet forums took off plus I
didnt use them myself.....my antenna switching system wouldnt take the power
anyway. All any visitor or guest operator saw was the NCL-2000 up to around
86 or later the LK-500. I still have that big Bird dummy load for testing
some 6M conversions for folks that do EME.
** Anyway 4x1 building was a common topic on here in the late 90's.
Carl
>
> later.... Jim VE7RF.
>
>>>
>>> Carl
>>> KM1H
>>>
>>>
>>> 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.
>>>
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