Minelab SD, GP, & GPX Classroom Forum

Hello,

I wanted to share my new booster/battery setup with you. I was tired of being tied to the machine by using the stock harness, and I wanted an inexpensive source of backup batteries. This setup allows me to use batteries designed for RC cars. These batteries are available at hobby shops everywhere and come in some large capacities. I've been using 5000mAH batteries, but recently bought an 8200mAH one. I estimate the total run time of 8-9 hours. The other good thing about RC car batteries is the availablity of some nice and FAST chargers. I am using one from my RC car racing days that works great.

I also wanted to boost the headphone volume, and allow speaker use if desired. I have tested the unit with several pairs of headphones, and I have also driven 4 and 8 ohm speakers with it. The sound is crisp, clear, and plenty loud. The amp is capable of almost 2 watts into a 4 ohm load. I am giving the audio a 6dB boost within the amp, and I'm controlling the volume from the GPX control box. I didn't feel a need for a volume knob.

Hope you like,

Best Regards,
Brian

Looks interesting. Couple of questions.... What are you using for the amp? Does it have a volume control on it? How much did this cost to create?

Thanks!

The amp was designed by myself including the Printed circuit board. It is a fully differential design, input and output so the amp has great performance characteristics. I did not incorporate a volume adjustment. The gain of the amp is fixed and volume can be controlled using the GPX target volume and volume limit functions. The overall volume is noticeably higher than running headphone from the stock battery and is in the ballpark of the stock batteries internal amplifier. I havent figured out total cost since I had many of the parts already. The circuit board was pricey since I only ordered a couple. Overall it probably cost me a few hundred. Well worth it for me since my harness can now go in the closet permanently! Also, I can get new batteries for cheap.

Best Regards,
Brian

Thanks Brian! Looks like a great setup!