This seems kind of small, but as long as it works.  are you sure it is 
pico?
73
Butch
WA0VJR

On Wed, 9 Feb 2011, colin McDonald wrote:

> yep....or a 4.7 peko ferrit ceramic cap is more appropriate apparently for
> 1.8 to 30MHZ.
> I've used it and it seems to work.
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "Butch Bussen" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, February 09, 2011 4:06 PM
> Subject: Re: interesting RF problem in the shack
>
>
>> Here is a g trick we use to use years ago.  For a long ground wire, take
>> a piece of coax, use center wire for the actual ground, and bypass each
>> end to the shield with a .001 cap.  It works.
>> 73
>> Butch
>> WA0VJR
>>
>> On Tue, 8 Feb 2011, Lloyd
>> Rasmussen wrote:
>>
>>> I think that the 4.7 pF capacitor is bogus.  The capacitance between
>>> center
>>> conductor and shield of even a few inches of coax is more than that.
>>>
>>> But creating a quarter-wave ground "counterpoise" connected to the
>>> station
>>> ground often helps, as mentioned in a previous message.  The far end of
>>> the
>>> wire might be hot, so don't put it where people are likely to come in
>>> contact with it.  For 20 meters, a quarter wavelength is about 16 feet.
>>> This would be the length from whatever you consider to be your station
>>> ground; perhaps the back of your amplifier.
>>>
>>> Lloyd Rasmussen, Kensington, Maryland
>>> Home:  http://lras.home.sprynet.com
>>> Work:  http://www.loc.gov/nls
>>>
>>>> -----Original Message-----
>>>> From: For blind ham radio operators
>>>> [mailto:[log in to unmask]]
>>>> On Behalf Of Gale Conard
>>>> Sent: Tuesday, February 08, 2011 12:17 AM
>>>> To: [log in to unmask]
>>>> Subject: Re: interesting RF problem in the shack
>>>>
>>>> Here is something I saved from a previous discussion about grounding.  I
>>>> haven't tried it, but several hams have testified that it has worked for
>>>> them.
>>>>
>>>>
>>>>
>>>> Hi list:
>>>> i think it was John who was saying that he has some grounding problems
>>>> being on the second floor.
>>>> I found a good method of helping to get rid of some of the floating
>>>> ground problems.
>>>> You use a peace of RG58 coax and put a 4.7  peaka farad seramic
>>>> capacitor across between the ground shield and center line of the coax =
>>>> on each end of the length you will need to go from your station to your
>>>> ground rod or an adequet ground somewhere.  Connect the center line of
>>>> the coax to ground and the center of the other end to the radio or to
>>>> your common station ground in the shack.  This is supposed to help to
>>>> eliminate floating ground and keep all the extra RF going to ground
>>>> instead of coming back up your ground line.
>>>> Regards
>>>> Colin
>>>> ----- Original Message -----
>>>> From: "tom behler" <[log in to unmask]>
>>>> To: <[log in to unmask]>
>>>> Sent: Monday, February 07, 2011 7:57 PM
>>>> Subject: Re: interesting RF problem in the shack
>>>>
>>>>
>>>>     Steve:
>>>>
>>>> I used this exact same set-up out in Colorado before I came back to
>>>> Michigan, and before I installed the Windom.  In fact, it's what I ran
>>>> the
>>>> Cross-country Blind ops net with last year, without a grounding system
>>>> at
>>>> all.
>>>>
>>>> The only thing I can think of that is different here in Michigan would
>>>> be
>>>> the Windom installation itself.  But, the Windom is on a completely
>>>> different antenna port on my Window feed through panel, and on my
>>>> TenTech
>>>> manual tuner.
>>>>
>>>> I will try grounding the rig-runner by connecting it to the common
>>>> ground
>>>> in
>>>> the shack, and will also try your ferrite solution.
>>>> Admittedly, before the Windom became unusable, I don't think I ever used
>>>> the
>>>> DXCC back here in Michigan on 20 meters ever since we returned.
>>>> Therefore
>>>> it's inpossible for me to tell if the problem existed before without my
>>>> knowing it.
>>>>
>>>> 73 from Tom Behler:  KB8TYJ
>>>>
>>>>
>>>>
>>>> ----- Original Message -----
>>>> From: "Steve Forst" <[log in to unmask]>
>>>> To: <[log in to unmask]>
>>>> Sent: Monday, February 07, 2011 9:33 PM
>>>> Subject: Re: interesting RF problem in the shack
>>>>
>>>>
>>>> Tom,
>>>>
>>>> Grounding might not be a bad idea. Also,  if you have any ferrites
>>>> around, I would try clamping a ferrite on the line from the power supply
>>>> to the rig runner, and also the line from the rig runner to the radio.
>>>>    Maybe disconnect any other gear that is connected to the rig runner
>>>> to try and isolate the source.   Perhaps move the rig runner as far as
>>>> possible away from the amp.
>>>>
>>>>
>>>>
>>>> Have you worked that combo of antenna/amp/band before?  Did this just
>>>> pop up out of the clear blue?  If it worked fine before and now has
>>>> problems, what has changed in the station that you can  try reversing?
>>>>
>>>>
>>>> And I thought I had problems...
>>>>
>>>> 73, Steve KW3A
>>>>
>>>> On 2/7/2011 8:58 PM, tom behler wrote:
>>>>> Hi, all.
>>>>>
>>>>> Well, I know I'm going to get varying opinions on this one, but that's
>>>> ok,
>>>>> since I'm looking for a number of possible alternative causes and
>>>>> solutions.
>>>>>
>>>>> As many of you know, I have gone back to using my Alpha Delta DXCC
>>>> antenna
>>>>> as my HF antenna, until my Windom, which took a dump on Saturday, can
>>>>> be
>>>>> resurrected.
>>>>>
>>>>> The DXCC works great on 40 meters with both 100 wattts, and my
>>>>> Ameritron
>>>>> AL811H amplifier.  However, when I went to do the Cross-Country blind
>>>> ops
>>>>> net on 14.258 yesterday, I had an interesting experience.  Things
>>>>> worked
>>>>> great with 100 watts, but when I kicked the amplifier in, and tried
>>>>> running
>>>>> things on the usual 600 watts, I ran into problems.  As soon as I keyed
>>>>> the
>>>>> mic, the protective circuit in my Rigrunner tripped, and everything in
>>>> my
>>>>> station went silent.
>>>>>
>>>>> I have no other indications of RFI anywhere else in the house or the
>>>>> shack.
>>>>> In addition, my SWR's are good with the DXCC on 20 meters (about 1.5 to
>>>> 1)
>>>>> without the tuner, and obviously just as good with the manual tuner.  I
>>>>> use
>>>>> my usual procedure to tune the amp, and everything works there as well,
>>>>> giving me forward and reflected power readings I would expect.
>>>>>
>>>>> Could anyone tell me what you think is going on here?  Do I still have
>>>>> a
>>>>> grounding issue of sorts, even though I've gotten no indication of
>>>>> grounding
>>>>> issues with other applications?
>>>>>
>>>>> Other than reducing power, is there anything anyone can suggest for me
>>>> to
>>>>> do
>>>>> to try to solve this problem.
>>>>>
>>>>> I was thinking of grounding the Rigrunner by connecting a ground cable
>>>>> from
>>>>> the cover of the Rigrunner to my common station ground, but just
>>>>> haven't
>>>>> gotten to it yet.
>>>>>
>>>>> It's just a strange problem, and only seems to occur on 20 meters with
>>>> the
>>>>> amp.  I never had the problem at all out in Colorado, where I had no
>>>>> station
>>>>> grounding system at all.
>>>>>
>>>>> 73 from Tom Behler:  KB8TYJ
>>>>>
>>>> 73,
>>>>
>>>>
>>>>
>>>> Gale
>>>> [log in to unmask]
>>>
>>>
>
>