TK 790/890 Dual band

[sfdten75k]

Had a TK 790/890 Dual band Dual head Installed in the new Chiefs vehicle by a Company who installed the Command Center in the rear of the Vehicle. Well they apparently only mounted the system and hooked up the external cables. They did not configure the radios to do dual band dual head. Everything is Wired correctly but can not program the radio. Im beleave they have not changed any jumpers inside. The Service manual does not explain using the KRK-8DBH for dual head and dual band. Does anyone know the inside radio config for the 790 and 890 to use as dual head daul band? Both heads are the full function Heads. Also I have no audio from the external speakers. I have the pins correct on the 12 pin connector on the rear of the heads, but do I have to also have the loop jumer connected to the 9 pin on each Radio unit?
Thanks in advance
Ralph Nahigian
Smithfield Fire, RI

[sfdten75k]

I was able to use a TK-690 manual to get the diagram to config the resestors inside to get the radio to work. The only problem I have now is the front speaker is working with the front head, but the rear speaker that is connected to the rear head is not working. Sounds me by reading the manual is that nothing can be hooked up to the rear head, I have them pluged into pin 10-11. Shoud these be pluged into the 9 pin in the rear of the VHF unit? Everything thing else works on both heads just rear head speaker. Any help ???
Thanks
Ralph

[dmonty83]

nah...you can plug a speaker into both of the heads and have stereo if you want. I believe there is a mod that has to be done to that head in order for it to work. Not having the service manual in front of me I don't want to mislead you, but I believe that is your problem.

David