Connecting the Quadra (VA7OJ)

Quadra Interface Diagram for Ft1000MP and Mark V

Although the exciter in my HF station is an IC-756Pro, there are some close parallels. I shall try to address your questions, although I am unfamiliar with the FT-1000MP line.

1. The VL-1000 requires at least 80W of drive for correct auto-tuning or band switching. In the MP, Menu item 4-3 Exciter Drive Power - must be set to MAX. Also, the reflectometer at the auto-tuner output will report a HI SWR error for load SWR > 3:1. There appears to be a slight non-linearity in the power/SWR relationship of this reflectometer, so at full power the amplifier may report a HI SWR error for load SWR > 2.75:1.

If the tuner appears to run for a few seconds and then stops with an ERROR indication, this is a sign that the exciter is not sending the amplifier a carrier for tuning. With a Yaesu FT-1000MP or MkV as exciter, the tuning cycle consists of two processes:

A. The "Band Data 1" (4-bit DIN) cable is connected between the exciter and amplifier BAND-DATA 1 jacks. The 4-bit code sent to the VL-1000 on the "Band Data 1" cable sets the band switching relays to the band selected on the transceiver.

B. The "Band Data 2" cable (DB15 to RCA) must be connected between the VL-1000 BAND-DATA 2 jack and the MP's "REMOTE" jack to allow the next step to take place. In addition, Menu item 7-9 on the exciter must be set to "EL" (the default value). When you press the [F SET] or [TUNE] button, the amplifier keys the MP, which in transmits a CW carrier to the amplifier. The VL-1000's CPU counts the excitation frequency, and initiates band selection [F SET] or tuning [TUNE]. When the band-selection or tuning cycle is complete, the VL-1000 unkeys the MP. The TUNER screen of the VL-1000 displays 'COMPLETE' if tuning is successful.

When the auto tuner has been tuned on a given frequency, the VL-1000 will memorize the tuner settings. When you tune the exciter to that frequency range again, pressing [F SET] will set the tuner to the closest memorized tuning point. This takes less time than a full tuning cycle. (VL-1000 user manual, page 7).

If the "Band Data 2" cable is not connected, pressing [F SET] will have no effect. Pressing [TUNE] will start the auto tuner, but in the absence of a carrier the tuner will stop almost immediately with an 'ERROR' display.

3. The instructions for connecting the "Band Data 2" cable are on page 4 of the user manual. The reason for the RCA plug is to accommodate non-MP exciters. For use with an MP, cut off the RCA plug and connect a 3mm mono mini-phone plug as follows:

Corrected Jan 6 2007 and should now read:

Tip to Band Data 2 Pin 10
Sleeve to Band Data 2 Pin 9

Plug the 3mm plug into the "REMOTE" jack on the MP.

This will correct the problem of the tuner not responding, as described above.

Incidentally, if the rear-panel "REMOTE" switch is in the ON position, the exciter's POWER switch will power the VL-1000 up and down. (User manual, page 8).

4. The fans in the RF cabinet can cycle on and off, or run continuously at low speed, depending on ambient. They will speed up when the VL-1000 is keyed. The fans in the PSU cabinet cycle on and off. (User manual, page 10).

5. I would recommend at least 4 in. of clear space around the top, sides and rear panel (if possible), to ensure adequate air-flow. The feet should also be locked in the elevated position.

Hope this is helpful. Adam, VA7OJ/AB4OJ