[Elecraft] QUADRA and the K3

[Joe Subich, W4TV]

> Look for and sign up for the Quadra Yahoo group there has 
> been some discussion there on the lash up using band data 2 
> input. I believe there is a mod to the amp that activates 
> the [INPUT] #2 to act and switch the band data info from 
> the number 1 input which is a change Yaesu left out for 
> some reason.

The Quadra is designed to use the Exciter 1 RF input with 
Band Data 1 (the DIN8/262 jack) and the Exciter 2 RF input 
with Band Data 2 (the DB15).  The schematic shows that to 
be the case as well.   The only issue that prevents using 
the Quadra with two exciters and automatic band switching 
is that the TF outputs activate for both exciters at the 
same time. 

The TF Set issue appears to be a late in the game change 
(the relay that would have switched the TF signal was used 
to switch a resistor to ground vs. contact closure to 
ground in order to support the remote tune function on 
the FT-1000MP.  In addition the second TF (tune) outputs 
was used for the switched resistor instead of the second 
exciter output.  The ground vs. resistor issue is also 
the reason that the TF output needs to be changed for use 
with the FT-2000/FT-9000 since the remote (keypad) tune 
function was abandoned in those rigs in favor of a separate 
dry contact input. 

> I do not remember where I saw this mod posted or by who.

The K2ESE modification adds an external relay to restore 
the missing TF switching function.  It is available at 
mods.dk as well as the files area of the YAESUQUADRA 
group on Yahoo.  The mod is only necessary in order to 
use the TF function with two exciters and the Quadra. 

73, 

   ... Joe, W4TV 
 
  




> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of ka9zap
> Sent: Thursday, July 09, 2009 4:13 PM
> To: Elecraft at mailman.qth.net
> Subject: [Elecraft] QUADRA and the K3
> 
> 
> I'm using the Quadra amp I change bands using the RF sniffing 
> method which does work ok.
> 
> The Quadra needs to see at least 50 watts carrier
> The Quadra needs to show the K3 a good swr so I switch in a 
> dummy load 
> after the amp.
> If the radio shuts down because of Hi SWR the F SET method 
> will not work. I press the [F SET] switch on the amp putting 
> it into TRANSMIT then 
> press and hold
> [XMIT] / tune until the amp switches bands, only takes a 
> couple seconds.
> 
> Here is a link that you can use for the lash up you are looking for
> 
> http://www.ab4oj.com/quadra/w4uk.html
> 
> Look for and sign up for the Quadra Yahoo group there has been some 
> discussion there
> on the lash up using band data 2 input. I believe there is a 
> mod to the 
> amp that activates
> the [INPUT] #2 to act and switch the band data info from the number 1 
> input which is a
> change Yaesu left out for some reason. After this mod is done 
> there will 
> then be radio control
> from both band data inputs from two radios the control being switched 
> via the amp [INPUT]
> button.
> I do not remember where I saw this mod posted or by who.
> I have the PTT and the ALC connected to the Quadra from the 
> K3 the talk 
> power on ssb
> is much higher than my ft2k so the ALC is a must. Before I 
> connected the 
> ALC up even as
> low as 20 watt SSB on the K3 sent the amp into high output I have no 
> issues controlling the amp
> with the ALC from the D sub 15 pin connector, pin 5 and pin 15.
> 
> My K3 serial is #3142 its born on date is 6/13/09 for first 
> qso, the K3 
> works well with the
> VL-1000.
> 
> Regards
> Art
> ka9zap