+++++++++++++++++ From: "Pauli Nunez EA3BLQ" To: "Harry Yingst" Cc: Subject: Re: [Elecraft] Data Jack for the K2 Date: Thu, 29 May 2003 02:03:27 +0200 Hi Harry, Think you have my Digital PCB in mind. Please pay a visit to my Digital Interface page on website at www.qsl.net/ea3blq/ (Menu-> English-> Digital Interface) where you'll find plenty of information. For your and all's info, currently I have designed a much smaller PCB (3x5 cm) with the same features as the one shown in my website except muting, but I am waiting to receive the KDSP2 option I have ordered so as to construct and install it on my K2/100 and thus see if the installation of my new PCB is feasible and easy before making it available to all. Hope it will be soon. Should you require more info please don't doubt to contact me. Thank you. Thanks to Bob, N7XY, for his having referred you to my papers at the Elecraft's Tech Notes page. Best 73 Pauli, EA3BLQ K2/100 #1044 URL: http://www.qsl.net/ea3blq/ ea3blq at menta.net ea3blq at qsl.net ----- Original Message ----- From: "Harry Yingst" To: "Elecraft_Reflector" Sent: Wednesday, May 28, 2003 7:23 PM Subject: [Elecraft] Data Jack for the K2 : I'm looking to install a "Data Jack" on the K2 (Similar to the Aux Jack : on the Icom Radios) for use with SSTV, RTTY, PSK31, etc. that would : basically be line level audio In & Out + PTT. : : I recall seeing that someone had made up a board or kit that did this. : : I'd rather not re-invent the wheel nor do I want to use a "Rig blaster" : type of external box. : : Doas any one know where I can find this? : : Thank you, : +++++++++++++++ Date: Thu, 29 May 2003 09:17:22 -0100 From: "Julian (G4ILO)" Subject: Re: [Elecraft] Data Jack for the K2 To: "Elecraft List" I can live with swapping the mic lead and the audio input, so I just wanted a constant output audio feed. Following a tip from someone on the reflector that I've not seen published anywhere, I attached a 1uF electrolytic to the junction of R10 and the drains of Q1,2 and 3 on the KAF2, and connected a length of screened cable from this to a socket on the back panel. A solder tag on the KAF2 fixing screw makes a good anchorage for the braid. This works splendidly, so much so that I'm put off getting the KDSP2 because I don't believe it has a suitable audio take-off point and so it will involve a lot more work getting going on data modes again. 73, -- Julian, G4ILO. (RSGB, ARRL, G-QRP, K2 #392) G4ILO's Shack: http://www.qsl.net/g4ilo Harry Yingst wrote: I'm looking to install a "Data Jack" on the K2 (Similar to the Aux Jack on the Icom Radios) for use with SSTV, RTTY, PSK31, etc. that would basically be line level audio In & Out + PTT. -- snip -- ++++++++++++++++++ From: "Lyle Johnson" To: "Elecraft List" Subject: RE: [Elecraft] Data Jack for the K2 Date: Thu, 29 May 2003 06:36:56 -0700 Hello Julian! > I can live with swapping the mic lead and the audio input, so I > just wanted a constant output audio feed. I assume you mean an audio tap that is not affected by the settingof the AF GAIN control? > Following a tip from someone on the reflector > that I've not seen published anywhere, I attached a 1uF > electrolytic to the junction of R10 and the drains... > This works splendidly, so much so that I'm put off > getting the KDSP2 because I don't believe it has a > suitable audio take-off point... You should be able to tap either the junction of R17/C10 or R18/C14 in the same manner as you tapped the KAF2. Ths is a low source-impedance location designed to drive 20-ohm headphones. Or, if you wish to stay entirely out of the audio path that you hear (to avoid coupled noise back in, for example), you could tap your 1 uF capacictor to J2 pin 4 or 5. This is a so-called "line out" designed to drive 600 ohms, and has its own amplifier path within the DSPx CODEC so should be very well decoupled. Now you may order a KDSP2 :-) 73, Lyle KK7P ++++++++++++++++