Here’s how I opened up my Transmit (Tx) and Receive (Rx) on the Yaesu vx-170. Out of the box, this 2meter radio only works on 144-148Mhz. This quick procedure increases the operating range to 137-174MHz.
1. Take off the battery.
2. Remove the black sticker in the battery compartment to reveal this:
3. Next, you can either pop off the Resistor by putting an exacto blade under it and twisting, or you can just make a small cut in the circuit I’ve pointed out where to cut with the red arrow. Benefit of cutting the circuit and leaving the resistor is that you could just touch the circuit up later with a drop of solder and the radio will be back to 2meter only frequencies. That’s what I did.
The below picture shows my cut. 
4, Next, while holding down the PTT and the button under it at the same time, turn on the radio. The screen will read “SETRST”.
5. Rotate the dial knob until it reads “ALLRST”, then press F (bottom left button)
6. Done. To make sure it worked, tune to a channel outside the 144-148 range and push the PTT. It read “ERROR” when I hadn’t sliced the circuit sufficiently.
Since that’s a zero-ohm resistor (equivalent to a wire), removing it is a better idea than cutting circuit traces. You can still restore the radio to its original operation by putting a blob of solder where the resistor used to be.
By: J-J Cote on September 1, 2009
at 12:54 pm
just “cut” the circuit,if you need to restore it use a pen ( grafit) instead of solder ( i am not joking,try it
)
By: mopje on September 12, 2009
at 2:44 pm
Zero Ohm resistor? Why would you put a zero Ohm resistor at all??
By: Fuif on September 22, 2009
at 7:12 pm
This is how electronics designers make things optional. If that circuit is connected, the microprocessor does not allow transmitting on the non-ham frequencies. If it isn’t connected, then it does allow it. It’s like putting in a switch that’s designed to be in only the open or closed position, rather than flipped by the user. If they are making a batch of radios for sale to someone authorized to use the non-ham frequencies, they would build them without the resistor in place. The whole point of a zero-ohm resistor is to be an optional jumper across a gap in a circuit. Since the machinery is already set up to handle things that are the size and shape of resistors, they make these jumpers look like resistors.
Basically, the engineer who designed this board already put a cut in the circuit for you, and installed a jumper across it that is easy to remove. That’s why the resistor is there. Making a separate cut is a weird thing to do. It’s like cutting a hole in the side of a cereal box to get the cereal out instead of opening the top.
By: jjcote on September 22, 2009
at 7:49 pm
Ahh Got it … Thanks
I can Understand both approaches, I guess you cut the line just because the resistor is hard to get out and put back if needed if you only have a basic solder gun .
By: Fuif on September 22, 2009
at 10:01 pm
The resistor is easy to remove. Takes very little heat, or you can just yank it off (or crush it). Replacing it with a blob of solder is actually easier than bridging a cut with solder, because of the solder mask.
By: jjcote on September 23, 2009
at 1:55 am
This modification also works on the Yaesu FT-270, a radio that is almost identical to the VX-170.
The modification procedure is almost identical. I opted to pop the jumper off with a knife.
By: Anonymous on October 20, 2009
at 12:01 am
i see you know about this radio.would you tell me why my radio is not transmitting.it is quite new.i can recieve but i can not transmit over 50 mt..the antenna is bended a little bit this can cause that ?anything else to check ?thx..
By: serdar on November 22, 2009
at 7:36 am
i have just opened up my FT270R and there wasnt any 0 ohm resistor in it. I can tx from 136 – 174Mhz.
By: Kelvin on December 21, 2009
at 12:04 pm
Thanks. This works very well. Just using a kitchen knife to scrape through the wire in the area illustrated worked well.
By: Dave on January 17, 2010
at 7:49 am
Have a new FT-270 and anxious to give this a try.
By: KE5IFA on February 13, 2010
at 12:44 am
I’m fairly new to amateur radio, and I own a FT-270. I popped the resister/jumper off and it works great!
Couldn’t be happier. 73s!
By: anonymous on February 28, 2010
at 10:46 am
Tanks, I did not got any “error” or text it gos to 144,000 and after that i can go were i want
Tanks again.
SM7Z
By: Odd on March 8, 2010
at 3:34 pm