Mystery transformers .... anyone ?

[MartyMart]

Anyone have a clue what these may be, from a "Job lot" of stuff last year.
Battery for size, thay are twice as thick as it and about 5 x heavier !!
Te only markings are 977/965 on both.

Thanks ,
MM.

 

[gary o]

I have very similar one has 913 printed on it ....came from either EMI or Ferrograph semi pro reel to reel also have another that is similar with 295GT printed on it mine both work ok a mic to grid transformer.

 

[iomegaman]

The non-round one is definitely a voltage storage device...

 

[Curtis]

I pulled a mic input transformer from an old Ferrograph reel-to-reel recorder a while back, looks exactly like those ones.  1:5 ratio IIRC, no centre tap on either winding.  Pretty sure this is the right schematic, transformer is on the lower-left of the drawing.

 

[MartyMart]

Thanks guys, much appreciated and I'll be sure to use that square one as a storage device !!!

 

[gary o]

Cool thanks for schematic Curtis ....have you anymore info schematics on Ferrograph....A guy sold me two sets of guts in a bad way told me they were EMI both seem to be Ferrograph but different models I think one has 600 ohm OP tran too.....lookin at yr schematic I see EQ inductors there too.

Cheers.

 

[Rob Flinn]

Gary,

I might be able to help you with the Ferrograpgh diagrams if you let me know the model numbers.

 

[gary o]

Hi Rob all Im told is series 2.....Dont go out of yr way Rob it was only to find what parts I have outa these things I think they beyond repair & I have no tape transport for the ferrograph....Cheers.

 

[Curtis]

Hey Gary,

The site where I got that schematic has a lot of info, including the complete user/service manual:

http://www.morphet.org.uk/ferro/s2docs.html

And if you go back to here there's all sorts of stuff about other Ferrograph models too.

 

[rodabod]

If you end up in this situation with random transformers, I reckon your best bet is to measure them using documentation found here and elsewhere. It isn't tricky, and since you won't probably find a datasheet, should provide you with more information than you'll get elsewhere.

 

[gary o]

Wow thanks Curtis intersting site....Hi Roda can that be found in the meta Ive seen something about this recently cant remember why I didnt try it ....

 

[EvLoutonian]

I also have one of these from an old Ferrograph series 4 or 5 amplifier module.
(I'm not sure what it is, but I'm hoping it's

In fact, I'm keen to hear if anyone knows generally what's involved with converting these old Ferrograph units into a standalone mic pre.  I've been meaning to do it for ages! (about 4 years)

Maybe I'll post a new thread on this topic, as I'm sure others would be interested, too.

 

[EvLoutonian]

This eBay seller offers various types from this range (possibly salvaged from Ferrographs?)
eg. 977 type:
http://www.ebay.co.uk/itm/PARTRIDGE-977-MOVING-COIL-MC-STEP-UP-TRANSFORMERS-VINTAGE/321544135882?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122125356%26meid%3De8fd52eae39249b59333d8c87636eddb%26pid%3D100005%26prg%3D20140122125356%26rk%3D3%26rkt%3D6%26sd%3D321528437845&rt=nc