[Elecraft] Microham Microkeyer II, RFI in mike with my K3

[Joe Subich, W4TV]

On 2/17/2016 2:05 AM, Jim Brown wrote:
 >
 > Perhaps that's what you're selling now, and if it is, that's great.

The microHAM supplied cables have been the same from the very start.
Again, schematics are on the web site.  The cables consist of special
multi-cable bundles with six individually shielded coaxial cables and
one shielded four wire cable in a common jacket.  The outer jacket is
cut back and the individual cables "fan out" to the appropriate jacks
on the transceiver end.  The mic cable is separate and in the case of
the DB37-EL-K3R is two individually shielded coaxial cables.

Again, the cables/interfaces work without RFI if the installation uses
good engineering practice.  No active external interface will be 100%
"RFI free" if the user fails to keep the RF voltage well below the
levels of the desired signals (~5 mV for dynamic mic audio).

73,

   ... Joe, W4TV


On 2/17/2016 2:05 AM, Jim Brown wrote:
> Joe,
>
> Perhaps that's what you're selling now, and if it is, that's great. But
> what I described is what is at W6OAT. As it happens, I rode into San
> Francisco tonight with him to meet a visiting JA contester for dinner.
> He confirmed that what I wrote was an accurate description of what's in
> his station. He's agreed to grab a few photos that I'll be happy to send
> you if you would like to refresh your memory.
>
> 73, Jim K9YC
>
> On Tue,2/16/2016 5:54 AM, Joe Subich, W4TV wrote:
>>
>> Jim,
>>
>> On 2/16/2016 2:04 AM, Jim Brown wrote:
>>> Indeed, it would darn near impossible to do it right without starting
>>> from scratch withunit a properly made cable from the MicroHam unit to
>>> the radio, with each signal path having its own coaxial cable.
>>
>> Please confine your comments to areas where you are knowledgeable.  The
>> microHAM cables *DO* use a separate coaxial cable (or shielded twisted
>> pair) for each signal path.  The shields are connected to the shell of
>> the respective connector on each end of the cable.  With properly
>> designed transceivers, this design will minimize RFI issues.  When good
>> engineering practice is used in the station installation - including
>> antenna systems - there should be no RFI problems with a properly
>> implemented microKEYER II, MK2R+ or micro2R system.
>>
>> Schematics for every microHAM cable are available from the support
>> area at www.microham.com or www.microHAM-USA.com/support.html.
>>
>> 73,
>>
>>    ... Joe, W4TV
>>