1500BA Battery Adapter

for

Tektronix 1502, 1503, 1502B and 1503B Metallic Cable Testers

© Brooke Clarke, N6GCE
1500BA Proto1 w/ AA cells
1500BA Proto #1 in 1502

Background

The 1502 and 1503 plain version "A" ( i.e. no letter) Metallic Cable Testers (Time Domain Reflectometers) instruments from Tektronix were designed for field use with the assumption that they would always be powered by the battery pack.  This is reasonable because it's very difficult to make connection to the battery pack terminals when a battery pack is not installed.  So the A.C. line input was mainly designed to charge the battery pack.  To protect the battery pack from over charging and draining too far down in voltage the main power supply to the instrument shuts down if the battery pack voltage gets too high or low.  This means for the revision "A" (no letter) units, that they will not turn on without a good battery pack installed, even when plugged into the A.C. line.

I bought one of these rev. A units and so needed a battery pack, which Tektronix no longer supports, so made up one.  The 1502 and 1503 were designed many years ago and in the mean time battery technology has advanced a lot.  By using Ni-MH "AA" cells I'm getting the same run times quoted for the original battery pack.

Description

The 1500BA consists of a metal frame that supports the "AA" battery holders providing 9 each "AA" cells.  These must be rechargeable Ni-Cad or Ni-MH type cells since the A.C. supply in the 150xA or 150xB recharges them.  Trying to recharge Alkaline cells would not be a good idea. 

It may be that Alkaline cells can be used in a field application where no A.C. power is being used.  If so the run time may be much longer than you can get with rechargeable cells.  But caution is needed so that charging is not attempted.

No attempt has been made to seal the battery adapter and in fact it's quite open at the back.

15 Feb. 2004 - Proto #1 is working, but a couple of more features need to be added. 
  • A fuse that's easy to get and replace
  • A Power Pole connector to allow a 1500BA, without any batteries installed, to be used as an external DC power supply adapter.  This would allow powering the MTDR from a common "12 Volt" vehicle cigarette lighter socket.
There has been no interest in this product and it has been canceled.

Back to Brooke's Products for Sale, Test Equipment, Military Information, ElectronicsHome page

This is the  time this page has been accessed since since 15 Feb. 2004.