Sound City 50+ partridge schematic

[9VOLT1967]

Well I would like to return to the original source of the problem here. Does anyone know where I can find original color codes of these 50 watt partridge output transformers. I know there are 5 wires leading to the input circuit. Large black and yellow - Small Green, White, and Yellow. Any info on this matter I would be grateful. Thanks

[Structo]

Power or output?

These guys rewind them so they might be worth a shout.

http://members.tripod.com/tubes_tubes_t ... /id80.html

http://www.soundcitysite.com/sc_webpage ... page_3.htm

You probably know about this site.

http://www.soundcitysite.com/sc_webpages/sc_home.htm

[selloutrr]

I'm not sure what colors you are refering too. These are the colors used in all Sound City amps. If this doesn't help do you have the Partridge Transformer Part Numbers?

PT-Voltage Switch:
Orange-- 115V ( jumpered lugs on switch to 105V lug-- no seperate 105V tap on the amp here)
Yellow-- 225V
Red-- 245V

OT Secondary:
Orange--- 4 ohm
Brown-- 8 ohm
Yellow-- 16 ohm
Red--- 100V Line/NFB connection



Output Tranny
Primary Windings
Red -Plate
Black-Center Tap (HV)
Orange- Plate

Secondary
Red- 100v Line
Yellow-16 Ohm Tap
Brown- 8 Ohm Tap
Orange- 4 Ohm tap

Power Tranny
Primary Windings
Grey- Tranny Shield
Black- Common
Orange- 105v
Brown- 115v
Yellow- 225v
Red- 245v

Secondary Windings
Red- Heaters
Violet- Bias Supply
Black- High Voltage (HT)

[9VOLT1967]

These are close, but no brown availiable- only 5 wires as stated
2 large - black and yellow
3 small - green, red, white


Power Tranny
Primary Windings
Grey- Tranny Shield
Black- Common
Orange- 105v
Brown- 115v
Yellow- 225v
Red- 245v


Partridge Mains transformer
TG9875
H2138H

[selloutrr]

The best advice I can give is to contact partridge and ask tech support for the wiring diagram.

Your next option is to setup up a test jig and meter it

[9VOLT1967]

I have decided to keep stock transformer on 105VAC tap as it is and run a voltage diubler for the bias circuit. I will be dropping heater voltage a little bit to keep it with in tolerances. Thank you for all the great info on these amps!

[LD50]

If anyone ever searches this topic again I have some answers.

I have two versions of the Partridges in question, an old heavily lacquered version with yellow partridge labels and a newer unlacquered version, both are TG9875

Old is TG9875/H3712M
Primaries
Black (thick) 0v
Yellow(thick)120v
Red (thin) 240v
Grey (thin) screen)
On same side as the primaries is thin green wire which appears to be heater centre tap!

Secondaries
Black + Red = 360v
Black + Orange 316v
Green + Green (thick) 6.8v
Brown + Brown (thin) 33v

New is TG9875/A265
Primaries
Black 0v
Yellow 120v
Red 240v
White screen

Secondaries
Green+Green 6.8v
Brown+Brown 33v
Black+Red 360v
Thin grey wire is heater centre tap

Hope that helps someone else in their searches!

[pdf64]

Yellow label Partridge OT from early 70s Sound City 50+, stamped codes of TG9876 and H1192
Primary
Red anode+ (resistance 23 ohms to CT)
Black twisted pair CT
Orange anode- (resistance 23.4 ohms to CT)

Secondary
Red+ 100V (4.07 voltage ratio, resistance 5.3 ohms to Black) works out to an intended load of 200ohms
Brown+ 16 ohm (14.4 voltage ratio)
Green+ 8 ohm (20.1 voltage ratio)
Orange+ 4 ohm (29.2 voltage ratio)
Black- common (pair of varnish insulated solid core wires in back plastic sleeve)