Tektronix TDS 3014B - power supply by pass

[eripaha]

I bought this Tektronix TDS 3014B scope. It was sold to me as is. The story goes that it might have taken over voltage to one of its channels. Some one has clearly had a hack at it and its missing its mains power board that is supposed to supply 15volts rail to the battery board witch then power the scope.

My idea was to try to power it off the battery connection using external transformers. I hooked up 15VDC power supply directly to its battery pins that i probed to be the likely power pins and BINGO! The fan started but i got nonthing on the screen. It drains 1.5amps @ 15Volts and 2.0amps @ 12Volts.

Now i dont know where to go from here. Maybe it needs some sort of signal from the battery to fully boot up or something. Do you guys have any ideas?

The battery connector has 5 pins. What could the pins be? One is the ground. One is the +15Volts (or what ever battery can spare). What are the rest 3? What are they on other products?

[eripaha]

People always like pictures;

[eripaha]

Found this burn mark on the connector that should go to the AC power board.

Maintenance manual differs from my scope 

[dan3460]

I have a feeling that you cannot get a service manual or schematics for this scope. I also think that the power board possible supplies more than the 15V source, I will guess that there is a 5V and possible a 3.5 or something like that.

[eripaha]

I have a feeling that you cannot get a service manual or schematics for this scope. I also think that the power board possible supplies more than the 15V source, I will guess that there is a 5V and possible a 3.5 or something like that.

Im trying to power it from the battery connector. I know that if i want to replace the battery board i need to supply +15VDC -15VDC +5VDC lines as well  so i wanna take the short route and just pretend to be the battery.

I found this TDS 3000 series service manual but this does not match my scope
http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK%20TDS%203000%20series%20Service.pdf

(sorry for bad english)

[nctnico]

Be creative. That battery connector looks like one for a smart battery! Google for 'smart battery specification'.

[voltsandjolts]

Somebody in this thread had a similar problem and got the scope to run from 12V:

https://www.eevblog.com/forum/testgear/battery-voltage-and-for-tektronix-tds-3000-series-oscilloscope/

[MarkL]

Below is a picture of the battery connector in a TDS3054 with + and - labeled.  The TDS3014B would be the same.

I found that only the + and - power input was needed.  Of course the scope has no idea how much battery life is left.  And in fact, it doesn't even report that it's running from battery.

I made a small jumper that allows me to run the scope off a 5400mAh 4S hobby LiPo pack.  One end is an XT60 connector that mates with the battery pack, and the other is a TE (Tyco) 787613-1, which is what's in the Tek battery pack.  There's also a 7A polyfuse in series for safety, which is also in the Tek battery pack.  Photo below.

The scope doesn't try to charge the battery if it can't talk to it, but a series diode would probably also be a good idea for safety too, just in case.  I take the battery pack out after use and charge it on an external balancing charger.

If you're wondering, the AC supply works fine in this scope.  I was just getting tired of rebuilding the Tek battery pack with it's 10 NiCad D cells every few years.  It was always dead whenever I needed a battery powered scope.


If the battery input doesn't work for you, it's possible the TDS "B" version, or perhaps the later firmware, won't let the scope run from the battery input if it can't talk to the battery.

[Dave Wise]

My TDS3054B with v3.36 firmware runs fine on an external 15V power supply so it should be fine on a non-communicating aftermarket battery.  It pulls about 30W with the backlight on maximum.

nctnico, TDS3BAT/TDS3BATB/TDS3BATC do not conform to the Smart Battery Specification.  They use the Benchmarq one-wire "DQ" comm interface, and only to read gas gauge data.

[vam]

Thanks Mark

That exactly what I was looking for