Thank you for purchasing the our resistor calibration set. This set requires AC electronics and soldering
knowledge. Please make sure to follow the instructions outlined in this guide to properly calibrate your B&K 700 or
707 tube tester.
We HIGHLY recommend you restore and clean your tester electrically prior to calibration. Replacing resistors as
needed and replace all capacitors period
– no exceptions. Below are details that we recommend:
- Start with a known working tester if possible or at least one that has not been butchered. If purchasing off ebay, make sure
to look for detailed photos, signs of water damage or corrosion on the face of the tester. And hopefully you will not find an y
nasty surprises inside!
- Unplug your tester before cleaning!
- Make sure to clean all sockets and switches with Deoxit D5. Spray sockets and switches liberally. Let set for a few minutes
and then spray clean once again. When spraying and flushing out switch contacts, make sure press the switches several
times while flushing them out to insure the contacts are cleaned properly. With Rotary switches, rotate the switch while
cleaning. Do not forget to flush out the power switch, heater rotary switch and last, remove the fuse and flush out the inside
of the holder!
- We recommend spraying inside trimmers and potentiometers. Open cased wire wound potentiometers can be sprayed as
you move the potentiometer back and forth which helps clean the contacts
- We recommend you take loose and pry-open the sensitivity pot and spray clean while rotating
- Check to make sure all sockets hold a tube firmly. If loose, you can use a pick tool to gently re -position the female pins in
each socket if required or replace each socket if needed. Use socket savers on sockets you plan to use on a regular basis
- We recommend you use a variac and set AC line voltage to exactly 117V during calibration. Make sure large electronics
are not running in the house while calibrating such as air conditioners or electric heaters. They can alter line voltage seve ral
volts when running, especially if your home or shop has older electrical.
- Test or have tested the 6BN8 and #83 tube. We highly recommend you replace the #83 tube with a solid state conversion.
#83 solid state / fused conversion directions located on the last page of this manual.
- We do recommend you solder the #55 lamp bulbs directly. While not absolutely required (these testers have worked fine
for ages not doing this) it is a very smart thing to do. At minimum, clean the bulb and socket with deoxit. Then clean again
and check every 5-6 months. ONLY USE VINTAGE BRASS BASE BULBS! DO NOT USE MODERN #55 BULBS, SIGNAL
VOLTAGE WILL LIKELY NOT DIAL IN IF YOU USE A MODERN EQUIVILANT!
- We recommend re-touching and re-flowing all solder joints one at a time, adding in a small amount of fresh no-clean solder
or quality solder of your choice. This is not required but can resolve a lot of hidden issues
B&K
700-707
Calibration
