TX-7800 frequency not right
- Thread starter E100
- Start date
The adj procedure is in the manual but you need special equipment for that.
I do not know this unit very well, but if it is like others, there is a tension spring in the tuning wheel attached to the var cap. Problem can be you unravel the string which is a PITA to put back. You can make a note of the dial string the way it is put on if you mess it up. You can put some tape around the tuning wheel so that the string does not unravel form the wheel, The pointer is attached to the string through some stranin reliefs, the string has to be taken off the point to move in the direction to re-cal it against the dial. None of this is easy, it takes some practice.
I do not know this unit very well, but if it is like others, there is a tension spring in the tuning wheel attached to the var cap. Problem can be you unravel the string which is a PITA to put back. You can make a note of the dial string the way it is put on if you mess it up. You can put some tape around the tuning wheel so that the string does not unravel form the wheel, The pointer is attached to the string through some stranin reliefs, the string has to be taken off the point to move in the direction to re-cal it against the dial. None of this is easy, it takes some practice.
Check your AM BAND before doing anything. Changing the needle position to accomodate the FM Band will cause the AM Band to be off. Most manufacturers have you turn the tuning dial all the way to the left until it hits the stops and note the Dial pin location (should be on ZERO on the LOG SCALE). If it's offset you need to loosen the strain relief's on the Dial pin and move the pin to match the LOG SCALE at ZERO. THEN do the alignment on both bands. If you never plan on using AM, you can check the dial pin location and adjust as necessary, then align the FM band. If it's anything like the TX-6800 the adjustments are made with a wooden spud and either opening or closing the fins on the Variable cap, @ 90mHz, like a SX-780. PITA for a good tech who knows what he's doing, almost impossible for a DIY. I'd just move the dial pin slightly left and call it a day.
