The home made E caller. How it was done.
Started with a huge coffeemug found along side the free way just after a truck stop exit.Cut the tail off and find a bucket and cut a sheet off the bottom to make a new cover.
To start with you'll need an Amp. I have found the little Radio Shack Amp (part #277-1008 = $12.99). I have experimented with this and other amps and dollar for dollar this little amp works, provides all the needed volume for about 90% of the calling you'll ever need, and the 9 Volt transistor Battery seems to last forever (provided it is not left on when not in use for days on end).
This little Radio Shack Amp actually is in a small plastic housing and there is a little 2" speaker inside the housing. The first thing I do is to remove the amp circuit board from the original housing. Next (through trial and error) I find the sweet spot on the volume control (on off switch volume control) at which the volume does not get any louder by turning the volume past that point, but rather just increases amp hiss/noise. I then remove the volume wheel from the volume control and hot glue the volume control in a
fixed position.
Since we have disabled the On-Off Switch on the amp, we need to wire in a separate On-Off Switch (Radio Shack #275-1565 = $2.59 ea). I also like to wire in a small LED Indicator Light to help in not leaving the Amp turned on when not in use (Radio Shack #276-084 - $1.99 ea). One wire from the LED Indicator Light and the Red Wire from the Amp Circuit Board get soldered to on terminal on the On-Off Switch.
The positive lead from the new 9Volt Battery Connector (Radio Shack #270-325 = $1.99 per pck of 5) gets wired to the other terminal of the On Off Switch. The negative wires from the new Battery Connector, Amp Circuit Board and
LED Indicator Light all get soldered together.
Next is the patch cord to go between the Amp and the Sound Source*** (Radio Shack #42-2497 1' patch cord** with 1/8" Stereo Plugs on each end = $4.29) and the sound source. You can get a premade 6' patch cord also if you need to have the sound source farther away from the amp.
*** Sound source I used was a MP3 player sounds from Varmintal's.com
** I bought 50 feet to get the caller away from me.
Radio Shack items parts list
Radio Shack #277-1008, Mini Audio Amplifier/Speaker = $12.99ea
Radio Shack #275-1565, SPST Soft Feel Push on Push Off Switch = $2.59ea
Radio Shack #276-084, LED Indicator Light for Amp (fits 3/16" hole) = $1.99ea
Radio Shack #42-2387, 6 Foot Patch Cord 1/8" Stereo Plug on each end = $4.99ea
Radio Shack #270-325, 9V Snap Type Battery Connectors (Pkg. of 5) = $1.99ea
The speaker I have found to produce the absolute BEST sound is the Speco SPC-5 PA Speaker. These can be order online from Lashen Electronics, they are $8.42 plus shipping, but they have a minimum order of $25.00. This speaker comes with about 10 feet of speaker wire and a plug attached (or at least the ones I have used have) to plug the speaker directly into the Speaker Jack on the Radio Shack Mini Amp.
Any more questions ask. I may have thre answer. MYy MP3 player is a Sansa Clip. Had a Apple shuffle for a while but hated the thing.
Al
