Thanks Steve. 73
Ed K7UC
----- Original Message -----
From: "Steve Forst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, April 09, 2011 8:21 AM
Subject: Re: looks like it's back to the head scratching on my 20-meter RFI
Problem
> Hi Ed,
>
> I think Tom is using the Ameritron RB-704, which has a keying relay and
> isolates the amp from the radio. I think the rig keys the buffer and
> the buffer keys the amp and prevents any possible damage to the keying
> circuit in the radio.
>
> Here are 2 places to look for ferrites:
>
> https://www.amidoncorp.com/
>
> http://www.allelectronics.com/make-a-store/category/235/Ferrites/1.html
>
> A few years ago I loaded up at All Electronics when the snap on beads
> were $1.25 each, or 10 for 10$. Prices have gone up since then. The
> stock at All Electronics varies over time and a lot of times the mix of
> the ferrite is unknown. If you need a particular mix for a particular
> application, look at Amidon.
>
> 73, Steve KW3A
>
>
>
> On 4/9/2011 9:50 AM, Ed Malmgren wrote:
>> I guess I'm a bit slow but what is the buffer in tom's lash up for? and
>> also
>> Steve where is a good source for a variety of different sizes of
>> ferrites?
>> I haven't used those very often. Thanks, 73
>> Ed K7UC
>> ----- Original Message -----
>> From: "Steve Forst"<[log in to unmask]>
>> To:<[log in to unmask]>
>> Sent: Saturday, April 09, 2011 6:21 AM
>> Subject: Re: looks like it's back to the head scratching on my 20-meter
>> RFI
>> Problem
>>
>>
>>> Tom,
>>>
>>> I agree. You can get a cable on ebay for about 20 bucks. I'd be
>>> surprised if the rig buffer is your problem, but stranger things have
>>> happened. You could always add ferrites to the RCA cables between the
>>> buffer and amp.
>>>
>>>
>>> If it were me, I'd run the full set up, as is, on the second antenna and
>>> see if there is the same problem. If you isolate it to the DXCC, you
>>> are half way home. This would be a good time to have a dummy load that
>>> will handle full power from your amp, to see what happens when the
>>> antennas are out of the equation.
>>>
>>> BTW, a few months ago, you had mentioned an interest in adding a LDG
>>> break out box to your wish list. If you have one in the shack, use
>>> the supplied 8 pin din from the 480 to the box, then RCA cables to the
>>> amp. This way you get the buffer out of the system without spending
>>> money on a cable you may not need once you find the real problem.
>>>
>>> 73, Steve KW3A
>>>
>>>
>>>
>>> On 4/8/2011 10:56 PM, John Miller wrote:
>>>> You can get cables on eBay or I think amaratron now has them, where you
>>>> can
>>>> connect the radio directly to the amp and you don't need any boxes or
>>>> anything, probably cheaper on ebay and might be worth a shot.
>>>> ----- Original Message -----
>>>> From: "tom behler"<[log in to unmask]>
>>>> To:<[log in to unmask]>
>>>> Sent: Friday, April 08, 2011 9:40 PM
>>>> Subject: looks like it's back to the head scratching on my 20-meter RFI
>>>> Problem
>>>>
>>>>
>>>>> Hi, all.
>>>>>
>>>>> Well, Bob Heil checked out my Heil GM5 mic, Kenwood interface cable,
>>>>> and
>>>>> FS2
>>>>> foot switch in his lab with his TS480 and amplifier, and couldn't
>>>>> replicate
>>>>> my 20-meter RFI problem.
>>>>>
>>>>> So, it looks like it's back to the drawing board for me.
>>>>>
>>>>> You may recall that I had the original RFI problem when using my Alpha
>>>>> Delta
>>>>> DXCC antenna, and when using the FS2 foot switch, so, I think
>>>>> something
>>>>> is
>>>>> creating an RF ground loop somewhere.
>>>>>
>>>>> You also may remember that if I plug the amplifier cable on the foot
>>>>> switch
>>>>> directly into the amplifier relay jack, it partially keys the
>>>>> amplifier,
>>>>> even without my pressing the foot switch.
>>>>>
>>>>> I am considering four things to try when I get back home from
>>>>> Missouri:
>>>>>
>>>>> 1. Trying the original set-up on my Carolina Windom 160 Compact,
>>>>> since
>>>>> that
>>>>> antenna was not working when I initially experienced the problem.
>>>>>
>>>>> 2. Taking the ARB704 buffer box completely out of the circuit,
>>>>> although
>>>>> I'm
>>>>> not sure how I'm going to directly hook up my Ameritron AL811H
>>>>> amplifier
>>>>> to
>>>>> the remote jack on the TS480. The remote interface cable I now have
>>>>> has
>>>>> two
>>>>> mini-din plugs, while there is no jack to accommodate such a plug on
>>>>> my
>>>>> Ameritron amp.
>>>>>
>>>>> 3. Purchasing and installing the 1 to 1 line isolator balun from the
>>>>> wire
>>>>> man that Kevin suggests, at least for the Alpha Delta DXCC antenna;
>>>>> and
>>>>>
>>>>> 4. Making a 20-meter counterpoise wire like some suggest, with one
>>>>> end
>>>>> connected in the shack, and the other hanging out the shack window.
>>>>> Regarding that counterpoise wire, should it be 15 or 16 feet long, and
>>>>> where
>>>>> do I connect the shack end?--to the ground lug on the TS480, or to the
>>>>> common ground lug on my MFJ window feed through panel?
>>>>>
>>>>> If anyone has comments on any of these four strategies, or if anyone
>>>>> has
>>>>> any
>>>>> other suggestions of things to try, please let me know.
>>>>>
>>>>> Thanks, and 73 from Tom Behler: KB8TYJ
>>>>
>>
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