Instruction: Extract information from the supporting document to answer the given question.

Input:
Question: how do i modify this unit to transmit further
Document: This product does exactly what it claims, no more. Instructions are simple and easy to use. I like that this unit can run off AA batteries, and is about the size of a deck of cards. With the initial settings, I found it would only transmit about 15 feet, but adjusting the transmit power and finding a clear frequency are easy with instructions you can find online. There was a faint, high-pitched squeal in all transmissions, but hardly noticeable.
I had the original transmitter, the volume control went bad so I bought this new improved unit. To increase the transmit power you open the back and turn up the VR pot. I did this on my original unit, it worked great. C Crane says on it's site that you can do this, but not how. Must be some FCC rule. On the original unit the pot turned about 90 deg, and increased the power to overcome the other radio stations when I drove to work.
I could barely get the FM2 to transmit reliably across my bedroom floor, a distance of less than ten feet. I had tried the FM2 earlier in a downstairs room and was able to receive a signal the next floor up, but the received signal was noisy, due to the weak signal strength of the transmitter. I have had both an old Radio Shack transmitter and a small Chinese unit that performed very well in both circumstances, so when the vaunted C.C.
I can't get the xmtr to transmit more than a couple of feet....Something obviously wrong....HELP!I followed instructions to no avail...
I use this to transmit Sat radio from the kitchen to the deck and basement workshop. Being battery powered is very useful and once you adjust the settings, it works well.
I used the C. Crane FM2 Digital Full Spectrum FM Transmitter to transmit the sound from my TV to the radio in my hot tub. Works great.
Completely flawed. Does not transmit a reliable signal from room to room. It will transmit short distance where there is line-of-sight. If I can see the source, I can also hear the source.
I did the mod, and now it transmit FM throughout the house. Sounds good too. Now I can tune in concerts on Paladia for pool partys this summer, and transmit it throughout the house, garage, and patio.
This is my second C Crane Transmitter. It seems to have the best coverage of most others. I use it to transmit internet radio stations to the rest of my property. It has been very dependable. (I did make the necessary adjustments.)
It's pretty good after doing mods. Without mods it is too weak to transmit thru a bedroom wall. See you tube for variable resistor adjust-mod, then replace antenna with 5 ft long wire. Now you can use it the way it's advertised.
Answer: There is a small adjustment at the top of the circuit board when you open itOld model was higher one direction, new is the opposite direction. It works great when cranked up.