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Tektronix power transformer data

  This is a 120-120 from a Tek 535A

With the help of a few folks on DIYAudio I've captured some data on Tektronix power transformers used in classic oscilloscopes and other vintage tube test equipment.

These transformers make excellent tube amp power supply transformers.  Sometimes you can pick up a Tek 545 scope or something similar for almost nothing.  Working or not, the power transformer is almost always good - they were built like tanks!

Here's some data:


Transformer 120-0103-00.
1 - 3 & 2 - 4 are 117 v Primary

10 - 11 6.5 v 2.5 A
13 - 12 6.5 v 5.0 A
18 - 19 6.5 v 8.0 A
29 - 30 6.5 v 4.0 A
7 - 14 270 v 200 ma
8 - 15 235 v 200 ma
9 - 16 122 v 100 ma
22 - 23 6.5 v 2.5 A
20 - 21 6.5 v 0.6 A
24 - 25 6.5 v 0.3 A
17 - 26 6.5 v 0.3 A
27 - 28 6.5 v 3.5 A
3 - 6 6.5 v 2.5 A


Transformer 120-296:
Pins 1-3 and 2-4 are primaries that can be wired in series for 240 volt
operation or parallel for 120 volt operation.

Pin 5-6 are 6.5 volts at 4.0 amps

Pin 7 is a "shield"

Pins 8-9 are 6.5 volts at 4.0 amps

Pins 12-13 14.0 volts at 2.0 amps
Pins 13-14 14.0 volts at 2.0 amps
(Pin 13 is the centertap of 12-14)

(Pins 15-16 100V ~100ma)

Pins 17-18 150 volts at 0.370 amps

Pins 19-20 157 volts at 0.210 amps

Pins 21-22 135 volts at 0.150 amps

There is a pair of white and red wires: 6.5 volts at 0.6 amps (insulated
for 3300 volts DC)

There are two pairs of yellow and red wires. Each pair is 6.5 volts at 4.0
amps.


Tektronix 555 oscilloscope 120-128:

234V mains: 1-4 (link 2, 3)
E/S screen: 27

Winding Voltage Current
9-10 208V 160mA
20-21 204V 50mA
11-12 126V 250mA
13-14 126V 250mA


Tektronix 555 oscilloscope 120-127:

234V mains: 1-4 (link 2, 3)
E/S screen: 21

Winding Voltage Current
5-6 6.3V 0.35A
10-11 6.3V 10A
12-13 6.3V 6A
14-15 148V 160mA


Tektronix 521 vectorscope 120-0498-00:

240V mains: 1-4 (link 6, 7) (Two windings 1, 5, 3, 6: 4, 8, 2, 7)
E/S screen: 9

Winding Voltage Current
17-18 6.3V ? CRT
15-16 180V ?
13-14 105V ?
12-11-10 28.5-0-28.5V ?


 Tektronix 545

The windings for the transformer 120-0140-00:
18 - 19 6.4 V 6.0 A
22 - 23 6.4 V 4.0 A
24 - 25 6.4 V 0.6 A Insulated for 1350 Volts
27 - 28 6.4 V 8.0 A
6 - 11 195 V 0.320 A
8 - 15 137 V 0.800 A
7 - 14 113 V 0.500 A
5 - 10 113 V 0.500 A
20 - 21 180 V 0.320 A
17 - 26 6.4 V 4.0 A
12 - 13 6.4 V 7.5 A
9 - 16 6.4 V 4.0 A


Corrected: Tektronix 533 oscilloscope

120-037 power transformer

 

The high voltage secondaries were stacked to produce higher voltages.

Primaries:

 115/230 V 60 hz.

Secondaries:

 120 V 240 MA

205V 170 M

130V 130 MA

150V 100 MA

210V 80 MA

6.3V 3.3A

6.3V 7.6 A

6.3V 7.1 A

6.3V 4 A

6.3V 600 MA HV Insulated

6.3V 3.8 A,

6.3V 3.7 A  


These from Rick Nasti:

 

Tektronix Part number 120-117

This is a factory original power transformer for the 502 oscilloscope. It has 120/240 volt primaries at 290 watts. It is 6" x  4 1/2" x 4". It weighs 14 pounds.

This is a factory-original transformer which can be used to replace a defective unit in any 502 or 502A oscilloscope. It can also be used for hi-fi audio or ham radio applications. Tektronix power transformers were built in-house and guaranteed for the life of the instrument. It has primary/secondary shielding.

This transformer has five 6.3 and one 5 volt volt heater windings. Two of the 6.3 volt windings are HV insulated for crt filaments. It supplies the following RMS plate voltages:  19 CT, 350 CT, 440 CT, and 800 CT.  These may be connected in series for various plate voltages. There are two primary windings which may be connected is parallel for 100-150 volt line operation. They may be connected in series for 200-250 volt line ranges.

NEW 2/24/08 - From Jur van Slingerland:

 

I have some information about the Tektronix transformer 120-117 mentioned on your site.  It's not complete but I think it can be useful to others.  I connected the transformer and did some measuring:

 

pins 5-5                 6.7V

pins 7-8-9             355V CT

pins 10-11-21       10V CT

pins 12-13            5.6V CT

pins 14-15-16       446V CT

pins 29-17-30       800V CT

pins 18-19            6.7V

pins 22-23            6.7V

pins 34-35            6.7V

pins 27-28            6.7V

 

Pins 1, 2, 3, &4 and pins A, B, C, D are used for primary voltages.  Pin 20 is a mystery to me (maybe a electrostatic shield?)

 

It looks like there are four 6.3V windings an two 5V heater windings (there are 2 GZ34's in a 502/502A) instead of just one.


Tektronix Part number 120-120

This is a factory original power transformer for the 545A oscilloscope. It has 120/240 volt primaries at 1 KVA 500 watts. It is 6" x 5" x 4 1/2". It weighs 18 pounds.

This is a factory-original transformer which can be used to replace a defective unit in any 545A oscilloscope. It can also be used for hi-fi audio or ham radio applications. Tektronix power transformers were built in-house and guaranteed for the life of the instrument. It has primary/secondary shielding.


This transformer has six 6.3 volt heater windings. One of the 6.3 volt windings is HV insulated for crt filaments. It supplies the following RMS plate voltages: 204, 141, 115, 117 and 186.  These may be connected in series for various plate voltages. There are two primary windings which may be connected is parallel for 100-150 volt line operation. They may be connected in series for 200-250 volt line ranges.


Tektronix Part number  120-0431-00

This is a factory original fully EMI shielded power transformer for the 556 oscilloscope. It has 120/240 volt primaries at 1 KVA 840 watts. It is 7 1/2" x 4 5/8" x 4 7/8". It weighs 25 pounds.

This is a factory-original transformer which can be used to replace a defective unit in any 556 oscilloscope. It can also be used for hi-fi audio applications. Tektronix power transformers were built in-house and guaranteed for the life of the instrument. It has external magnetic and EMI shielding as well as primary/secondary shielding. All factory leads are intact with connectors.

This transformer has five 6.3 volt heater windings. Two of the 6.3 volt windings are HV insulated for crt filaments. It supplies the following RMS plate voltages: 116, 126, 130, and 145.  These may be connected in series for various plate voltages. There are two primary windings which may be connected is parallel for 100-150 volt line operation. They may be connected in series for 200-250 volt line ranges.


Here's some measured data on a transformer from a Tek 545A (XLS file).  Not sure which part number it was.  The 535, 545, 535A and 545A are pretty similar, I think...