Custom Electronics Service ?

[AJAJ]

I am trying to find someone who can build simple electronic devices I need now and then. These things are not for production, just for my use. (I'm a crime scene analyst involved in ballistics and other forensic research). I don't need engineering or custom PCB's or polished housings; most of what I need can be constructed from modified off the shelf items. I used to know a retired EE who built things for me but he passed away.

Right now I need a simple talkback paging/PA system. One station with an intercom type box (with speaker) and a push to talk switch that will talk over a (10 watt or so) loudspeaker in a different area (wired, not wireless). And the people in the other area can just shout back at the speaker (without pushing a button) and be heard at the master station. (Yes, there are many similar systems commerically available but most work through a telephone system or are complex items with many stations or Radio Shack type intercoms that don't have the loudspeaker power I need.)

I thought I recalled ads from people willing to build such things in Nuts & Volts but I can't find them now.

Thanks,

Alex Jason
[email protected]

[Externet]

Hello and welcome.
It has been a loooong time since I played with those.
From what I remember, it is an audio amplifier with output stepped up to 70V, The speaker end picks voice and the normally closed contact of the base 'unpushed' button routes its signal to the amplifier input that selects the local base speaker.
When the button is pushed, its contacts route the local speaker to the amplifier input and the amplifier output is routed to the remote speaker.

Nice project!
Miguel

[jwax]

How about an off-the-shelf PA system with the speaker in the remote area, and a baby monitor in the remote area to talk back to the base?
An option would be to "Silence" the baby monitor pickup (from the base?)
Loads of possibilities!
John

P.S. Welcome to the forum AJAJ!

[psycho]

To answer your main question, you might try looking for a local ham radio operator. Most of them (esp. the old timers) know quite a bit about electronics. If I knew where you are from, I would look.

You might look in your phone book for places that sell radio equipment (for ham radio) - tho there probably won't be any listings. Try Two-Way radio, too. Also any place that sells electronic components - the people who work there may know someone who could help. You could try radio-shaft, too - maybe one of their customers is into electronics...

Hope it helps,
Kevin

[Lenp]

AJAJ
Check your email!
Len