[Elecraft] AD-1-K doesn't have blocking capacitor, Heil claims

[Dick Dievendorff]

http://heilsound.com/amateur/products/headphone-adapters/index.php

Some Heil ICOM adapters have DC blocking capacitors. These are adapters like
the AD-1-I.  I've used these when I had ICOM equipment, and I have a few
lying around here.

Some Heil ICOM adapters are designed for microphones that require bias,
including Heil's "iC" series.  These are adapters like the AD-1-iC.   These
don't have a blocking capacitor.

Heil says the Kenwood (AD-1-K) and Yaesu (AD-1-Y) adapters never contained
DC blocking capacitors. Therefore if you use the AD-1-K for an Elecraft rig,
you choose bias or no bias depending on the K3's microphone configuration
setting.

I didn't intend to make any claims about ICOM-specific adapters or
microphones in the note - I only wanted to determine if any AD-1-Ks had
blocking capacitors.  Bob said they didn't.

This means (to me) that I should be able to use Heil's AD-1-K for my
Elecraft K3 for any microphone that has a 3.5 mm plug, whether or not that
microphone requires bias, and the K3's configuration menu sets it up
appropriately. If I had learned that some AD-1-K microphones had blocking
capacitors (and I've seen that stated), then I'd be more careful about
recommending the AD-1-K.

Dick, K6KR

-----Original Message-----
From: Don Wilhelm [mailto:w3fpr at embarqmail.com] 
Sent: Friday, February 24, 2012 2:57 PM
To: Dick Dievendorff
Cc: elecraft at mailman.qth.net
Subject: Re: [Elecraft] AD-1-K doesn't have blocking capacitor, Heil claims

Dick,

I don't want to argue with the person who should know his own products, but
there *is* (or was) a Proset-iC that had an electret element which needed
bias.
So if the ICOM adapters have the capacitor, how does the ProSet-iC work with
an Icom transceiver.
Are you certain he was referring to the adapter for the ProSet?

73,
Don W3FPR

On 2/24/2012 2:53 PM, Dick Dievendorff wrote:
> Bob Heil just told me that only the ICOM Heil adapters have blocking 
> capacitors.
>
>>> Of course NONE of the Kenwood or Yaesu have any blocking caps as 
>>> none of
> their inputs have phantom voltage (thank goodness)
>
> Dick, K6KR
>
>