The VRX-1 receiver kit uses a TDA7052 audio amplifier IC, which is a bit different from your run-of-the-mill LM386. Because of its push-pull output, if you use a phones jack, you must isolate it from ground. This isn't something you have to worry about if you use a non-conductive enclosure or if you have an isolated phones jack. However, more often than not, you won't have an isolated jack, and many of the enclosures that we use are metal.
This little hint will allow you to modify a "standard" grounded ring phones jack with a conductive enclosure (such as the 4SQRP Clear Top Tin, like the one I used).
Bill of Materials
- 3.5 mm phones jack
- Small length of 3/8" OD (1/4" ID) Polyethylene Tubing
- 1/4" nylon washer
- CA glue (optional)