I have a dual band uniden uh090 cb radio. This cb does both am and uhf however it was only sold in aussi and has the 27 Mhz band and not 26 Mhz as in Nz. I would like to convert it to the 26 Mhz .
Does any body have service manual or schematics for this Cb. Or has anybody done this.
The uh090 is the little brother to the uh 095sx in which you just add or remove a link to change the frequency.
Any help would be appreciated.
Nathen
Auckland Nz
Aussi uniden uh090
Re: Aussi uniden uh090
So the am is using a BU2630F Pll which is controlled by a controller chip else where on the board. It has a 10.24 Mhz oscillator across the Xin and Xout pins.
The datasheet indicates the receive and transmit frequencies are calculated by using a reference frequency the oscillator and data from the controller
So If I change the oscillator frequency will that allow me to move the frequencies down. Can any body tell me where the reference frequency comes form.
Cheers Nathen
The datasheet indicates the receive and transmit frequencies are calculated by using a reference frequency the oscillator and data from the controller
So If I change the oscillator frequency will that allow me to move the frequencies down. Can any body tell me where the reference frequency comes form.
Cheers Nathen
Re: Aussi uniden uh090
The reference frequency comes from a 10.240 Mhz crystal.
You CANNOT change this to mod the radio.
(10.240 divided by 2048 = 5 Khz) x 91 = 455 Khz, the IF frequency of the radio and the TX/RX frequency shift.
Therefore, changing this to anything other than 10.240 will cause the radio to transmit and receive on different channels!
You would either have to rewrite the firmware or substitute a new synthesizer circuit.
Either option would be far more expensive than buying a new radio.
Sell it on eBay to an aussie and buy a new one.
You CANNOT change this to mod the radio.
(10.240 divided by 2048 = 5 Khz) x 91 = 455 Khz, the IF frequency of the radio and the TX/RX frequency shift.
Therefore, changing this to anything other than 10.240 will cause the radio to transmit and receive on different channels!
You would either have to rewrite the firmware or substitute a new synthesizer circuit.
Either option would be far more expensive than buying a new radio.
Sell it on eBay to an aussie and buy a new one.
Re: Aussi uniden uh090
That's a shame These dual band radios are no longer available so buying another is not really and option. I will have to get 2 sets an am and a UHF sets and find space to mount them.
Re: Aussi uniden uh090
Those things were about the worst "radios" made in recent times, in the end we refused to repair them (guaranteed bouncers). Way too many problems to list here...These dual band radios are no longer available so buying another is not really and option
Do GME sell their "all controls on the mic" UHF radio over there? These work great and the "box" can be mounted out of sight, such as under a seat or under the centre console. That way you can only have one radio (the HF) on show.