[Elecraft] HF Digital interface for the K2...

[David Wilburn]

Sounds great.  I think I will patiently await the update.  Thanks again.

David Wilburn
dave.wilburn at verizon.net
K4DGW
K2 #5982


Don Wilhelm wrote:
> Ken and all,
> 
> I no longer have kits, but I have 18 boards available.  The output of the
> fixed audio board is isolated from all other signals in the K2, so
> connection to the board output will not have any effect on any normal
> function of the K2.  If you want a look, go to my website
> http://w3fpr.qrpradio.com.  I do have an updated method to mount the board
> between the front panel and the control board which is ideal for those who
> want to use no connectors and/or want the output signal to connect to the
> mic jack - the resistors and capacitors are laid down flat or low profile
> components may be used.
> 
> The input to the audio amp on my board is close to the equivalent of the
> signals appearing at J5 - I just chose to use the outbound side of the mute
> transistors rather than the direct product detector output - for some reason
> at the time, I wanted my fixed audio muted, and the connections were easier
> doing it the way I did.
> 
> There is no problem with using the output from J5 as suggested by MicroHam,
> except that it is a very low level, and the MicroHam interface has no
> amplifier - it simply feeds the balanced output through their box and on to
> the soundcard connected as a single ended signal - so they lose 3 dB by
> switching to single ended output and depend on the soundcard gain to
> compensate - it will work, but could reduce the signal to noise ratio at the
> soundcard input.
> 
> I suppose I will get a rash of requests for the board now <G>.  When these
> 18 are gone, they will be no more, but the circuit is easy to wire on a
> piece of perfboard, and I am considering an update to provide the K2 with
> both input and output for digital modes so you can plug directly to the
> computer soundcard (no interfece box required), but I do need to find the
> time to put something together.
> 
> 73,
> Don W3FPR
> 
>> -----Original Message-----
> 
>> I have Don's fixed audio mod in my K2 and it works
>> very well.  It's wired to the front panel mic
>> connector, which works perfectly when you use the
>> Tigertronics SL-1+ audio interface.
>>
>> I spoke to Don about MicroHam's using the audio
>> available from J5 inside the K2.  He didn't think it
>> was a good idea, but he can explain why better than I
>> can.
>>
>> 73,
>>
>> Ken Alexander, VE3HLS
>>
>>
>> --- Tom Hammond <n0ss at earthlink.net> wrote:
>>
>>> Don Wilhelm, W3FPR, offers a really nice fixed
>>> output interface for the K2.
>>>
>>> However, it may NOT offer output of the CW SIDETONE,
>>> since that comes
>>> in on a different input port to the AF amp and is
>>> not currently
>>> sampled by the fixed output amp.
>>>
>>> Contact Don at:  Don Wilhelm W3FPR <w3fpr at arrl.net>
>>>
>>> 73,
>>>
>>> Tom Hammond   N0SS
>>>
>>>
>>> At 11:18 AM 3/10/2007, Peter wrote:
>>>> Hi
>>>>
>>>> A small audio amp. and you have fixed audio level
>>> at the back.
>>>> http://www.pi4cc.nl/personal/pc2a/k2/
>>>>
>>>> Peter
>>>> PC2A
>>>>
>>>> Tony Lyon schreef:
>>>>> Jamie,
>>>>> Thanks.... Being able to connect to the J5
>>> connector looks like it
>>>>> will do the trick. I looked
>>>>> in the K2 manual and I noticed that the J5 AF
>>> output is derived
>>>>> directly  from pins 4 and 5
>>>>> of the NE602 product detector.
>>>>>
>>>>> So, my next question is:.
>>>>> Does the NE602  have enough output drive to drive
>>> the AF input of a
>>>>> RigEXpert?
>>>>>
>>>>> 73,
>>>>> Tony Lyon (KJ5XF)
> 
> --
> No virus found in this outgoing message.
> Checked by AVG Free Edition.
> Version: 7.5.446 / Virus Database: 268.18.8/717 - Release Date: 3/10/2007
> 2:25 PM
> 
> _______________________________________________
> Elecraft mailing list
> Post to: Elecraft at mailman.qth.net
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
>  http://mailman.qth.net/mailman/listinfo/elecraft    
> 
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>