Ex workshop spare parts and small manufacturing stock
ALL components were sourced through reputable local distributors such as RS Electronics, Farnell, WES and Rockby (Victoria) or direct from the manufacturer. This transformer was sourced originally from Altronics (old stock) but that company still sells a very similar (actually less versatile) transformer, their catalogue number is M5535C (Retail A$145) LOOK HERE
We used squillions of these back in the day, such a great "general purpose" audio amplifier power transformer.
Very nice AC power transformer for solid state amplifiers up to medium output power (around 150W per channel). Provides 4x secondaries (all isolated from each other), two being grunty 35V windings (wired in series = 70V) AND 2x 15V windings for the preamp stages, especially suited to (but not limited to) Op amp dual rail supplies. Ratings are FULL LOAD
2x 35V @ 4.2A under full load
2x 15V @ 0.5A (500mA) under full load
Yes, these are BRAND NEW, never used (old shelf stock) and VERY LOW COST - I am well out of manufacturing now and taking it easy, I just want to find new owners for these, great for that special "project amp"
HINT: Get a "group" together and buy more than one transformer and the automatic discounts "kick in" which provide substantial savings over the already very low price!
But wait there's more!
Purchasing more than 2 transformers will "trip" my "special shipping prices" - shipping around Australia will be FREE when purchasing 2 or more transformers.
POWERTRAN - Toroidal Power Transformer
Sourced through Altronics
Fully Australian Standards safety approved
Model: MB5535
PRIMARY:
240V 50Hz ONLY (NO windings for other international AC supplies)
SECONDARIES:
2x 35V @ 4.2A
2x 15V @ 0.5A (500mA)
NO mounting hardware supplied (rubber or plastic discs, metal disc and central bolt) These are ex manufacturing stock toroids and we had our own supplier for the mounting kits. Look around online and there are numerous suppliers of these kits e.g RS Electronics, Mouser to name just two
One label on the side
MB5535 300VA
REQUIRES 5A PRIMARY FUSE
C/S No. CS/815/Q
WWW.ALTRONICS.COM.AU
POWERTRAN
To the right of the above information is the technical information
regarding windings and which colours are used
Quad (Isolated) secondaries.
All windings are colour coded and reasonably easy to identify although it is made a little confusing by using the same sheath colours for different windings!
The transformer is clearly marked on the side as to which wire does what, and the colour. Problem is, POWERTRAN have duplicated the secondary colours so there are two Reds, two Whites, two Orange and two Blacks!
Reasonably easy to figure out which wire has what on it! I personally like the HARBUCH colour scheme better but if you are careful, you will have no issues with these POWERTRANS.
Look for the heavier gauge wire on the secondaries, those are the 35V outputs, the thinner enamelled copper wire is the 15V outputs
First two wires (Blue & Brown) are the primary winding, 240V AC input and the secondary wires follow in a circle from those primary wires.
Physical measurements:
110mm diameter
Potted centre (epoxy resin filled) with a 5.5mm centre hole for the bolt (not supplied)
65 ~ 70mm height (the higher number is including the wires)
All flying leads 175mm length
All secondary wires are solid core, enamelled copper with pre-tinning at the end
Primary leads enamelled copper wire, solid core
High current 35V Secondary leads 1.2mm diameter
Medium current 15V secondary leads 0.65mm diameter
Transformer has a packed weight of 2.5Kg
COSMETIC CONDITION:
NEW, never used
TESTING:
To confirm the transformer is functioning properly, I have made some simple "open circuit/no load" tests on each transformer I have available.
Secondaries 35V: Measures 37.6V NO LOAD
Both 35V secondaries measure exactly the same
Secondaries 15V: Measures 15.2V
Confirmed total isolation between Primary & Secondary windings (NOT an auto transformer!) and between each secondary winding.
