Old Hammond 1640SE OPT

[albertli]

Hi guys,

I have a pair of old 1640SE sitting on my work bench for years and I'd love to make use of it, but I lost the connection data. There are Red, Blue/yellow and Blue on one side and Yellow, Green, Green/yellow and 2 Blacks on the other. Any help would be much appreciated.

Albert

[pieter t]

Albert,

Primary side: red B+; blue/yellow ULtap; blue plate.
Check the primary side by measuring some 100+ ohms between red and blue.
Secondary side: black common; green 4 ohm; yellow 8 ohm; green/yellow 16 ohm.
Other schematic I found indicated white for 16 ohm so you have to measure to be sure.

[VictoriaGuy]

Albert-
If you can't find the info you need, contact Hammond (in Guelph,ON) directly. They were quite helpful (including mailing photocopies of old catalog pages to me) when I was trying to figure out the wiring/specs for some older interstage transformers.

John

[century tek]

FYI, that's a push/pull (not UL) tapped output transformer. Red is CT (B+), blue is plate #1, and blue/yellow is plate #2 (if using 6V6 type tubes, pins #3).

[albertli]

Thanks guys.

pieter t

I'll check them accordingly.

VictoriaGuy

You're right. I certainly will ask them to send me a copy for keep.

[smoking-amp]

I recall that the SE series had the same secondary hookup as the 1650 P-P xfmrs. See here:
Schematic & Hook Up Data (all models except 1645 - see below):

Hammond Mfg. - "Classic" Push-Pull - Tube Output Transformers - (1608 - 1620, 1645 & 1650 Series)

[albertli]

Originally Posted by smoking-amp

I recall that the SE series had the same secondary hookup as the 1650 P-P xfmrs. See here:
Schematic & Hook Up Data (all models except 1645 - see below):

Hammond Mfg. - "Classic" Push-Pull - Tube Output Transformers - (1608 - 1620, 1645 & 1650 Series)

It matches all color wires on my opt. Is there any way I could check with my multimeter.

Thanks

Albert

[smoking-amp]

Yellow to Blk/Yel should be about 1.2 Ohms (after subtracting out the meter leads Ohms)

Blk/Yel to Grn/Yel should be about .9 Ohm (" " ")

And Blk to Grn should be about .9 Ohm (" " ")

No continuity from Grn or Blk to the other set: Yel, Grn/Yel, Blk/Yel.

Make sure to rotate the bananna/lead connectors on the DVM first before doing such low Ohm measurements, or the contact resistances will overwhelm the readings. Then short the meter lead ends together to get the lead resistance, to subtract out from the winding readings.

[albertli]

Originally Posted by smoking-amp

Yellow to Blk/Yel should be about 1.2 Ohms (after subtracting out the meter leads Ohms)

Blk/Yel to Grn/Yel should be about .9 Ohm (" " ")

And Blk to Grn should be about .9 Ohm (" " ")

No continuity from Grn or Blk to the other set: Yel, Grn/Yel, Blk/Yel.

Make sure to rotate the bananna/lead connectors on the DVM first before doing such low Ohm measurements, or the contact resistances will overwhelm the readings. Then short the meter lead ends together to get the lead resistance, to subtract out from the winding readings.

You're great. I have the numbers almost exactly the same as said.
The first set of three on top, yellow/Blk-yellow 1.2 ohm, Green-yellow/ Blk-yellow 0.9 ohm. The bottom set of two, green/Blk 0.9 ohm.
I put the green-yellow and green together and Blk-yellow/Blk together ( as said on hook-up data provided ), I now have 0.8 ohm with yellow and black. It supposes to be 8 ohm hook-up as of data.
On primary, Red with Black I have 82 ohm. Does it mean I can go ahead with this ??? Thanks

Albert

[smoking-amp]

I think you are set to go.