transformer

My current restoration project is a Sony STR-7065A. Aside from the usual problems (dirty contacts/pots, burnt out lamps, etc.), it has a very noticeable hum coming from the transformer. It's moderate when idling, but pushing it to max power into dummy loads gets it buzzing really loud. To be...

Hi everyone, Just after some input on transformer replacement on a Kenwood KA7300. Original unit has two 100v primary : 33v secondary center tapped transformers. (Japan import) I would like to replace the transformers with a 240v primary, but I am having trouble finding one with 33v...

Hello, I have switch on the back for the impedance - 8-16 ohm and 4-6 ohm. I have Pioneer HPM 700 - 8 ohm speakers and Elektronika 35ac-015 which are 4 ohm. I usually listen to the Pioneers. On the net I found that if I put the switch on 8 ohm the amp will have full power. If I put it on 4 ohm...

Hello all, I’m exploring a possible repair on a Pioneer SA-1490 receiver I got from a friend who insists it was working for him before giving to me. I’d like to save it from the recycle pile but it’s not working now. Two sentences about me. Although trained as a EE, I’ve leaned on more of the...

Transformer V/I output stage for DAC. The good engineers at ESS know there are one two people out there, that do high current things in low power places. Now they can sleep knowing their hard work making that possible, is put to use. The first transformer behaves as tone control, controlled by...

I had a go at building an HF-87 clone from scratch. Wound the output transformers from 3/4 stacks of microwave iron and 3d-printed nylon bobbins. Power transformer was wound from an old HIPOT transformer with another 3d-printed nylon bobbin. DIY walnut cabinet.

Yesterday, I received my new-to-me Pioneer SX-434. The ad on ebay said it was recently serviced and in good working order. The trouble is, I discover after plugging in that the only thing working are the dashboard lights. That makes sense because the transformer secondary that feeds the lamp...

Sub PSW650 Polk Audio primary transformer coil burnt. 110v. If your power grid is 110v (USA) and the sub is not working at all probably your primary(input) coil of the transformer has been burnt. Just use a simple tester to check the resistance on a receptacle of a Sub. The regular resistance...

So I'm trouble shooting a Yamaha amp that appears flat dead. It was working, was moved a few hundred miles and is now dead. Quick check with my multi-meter shows 120vac coming in, fuse fine, but from the first power filter board to the transformer I have 0 volts. I pulled the connector to the...

Hello! This is my first post so I will try my best to provide as much information as possible. I have a Grundig SO 132 stereo console which works mostly but I can’t get over that there seems to be an extra transformer and a loose tube. I was lucky to find the electrical schematics(IN ENGLISH!)...

hello. working in a au 717 wich need tons on TLC. short on DBT . i rebuid amp modules, short on DBT i removed power supply and disconected the amp boards. short on DBT. transformers, maybe blown? it is a multivoltage unit, once removed from amplifier, how could i conect or configure them to...

Dear experts, I need help knowing the resistances of the secondaries of a 999 transformer. After having obtained :banana:a multivoltage (heavy) :) transformer for my AU-999 100 VAC version to replace the (missing) original one, I would like to compare the secondaries with a good working unit, if...

Trying to troubleshoot a sx780. Lights up but stays in protection. Trying to swim upstream. No voltage readings on schematics for secondary side of transformer. 30v from red wires but 0v from white and brown outputs. White goes to capacitor assembly, brown to pin 21. Can anyone tell me what...

Looking for an experts help here. I found the Marantz SR-2000 receiver locally with blown fuse. Typical reason would be shorted output STK modules - checked them and indeed one was shorted. Replaced both STKs with STK082G (instead of original STK080G) and the unit worked fine for few days...

Hi I recently got this nice receiver but the transformer was taken out of it by someone. I purchased a transfoemer from e-Bay. #159-093 3527244 I wanted to know is the MAC 1900 transformer a multivoltage? I live in 220/240 AC area Thanks

Just wanted to throw this out there. I recently purchased a 374BX power transformer and on the secondary side the 50vac (violet) and one of the 375vac (red) were swapped. This not only could have roasted some equipment, it is a safety hazard. Their customer support was abhorrent and...

hello everyone I have a sx 3900 in which the DBT sends a short circuit when energizing, the unit has been restored and in particular the amplification section has been rebuilt according to the recommendations of the forum. The power transistors are the 2sc2922/2sa1216. and in particular the...

Does anyone know the output specs for the 2225 transformer? The service manual shows three AC inputs to the P800 power supply board, but I don't see any specification for their voltages. I can measure them on the unit as well, but would like also to compare those measurements to a spec.

The title says it all. I'm trying to hunt down a functional transformer for a Denon PMA-500V but I'm not seeing many scrapped parts on ebay. Any suggestions on where to locate one or is this a lost cause?

Hello I finally got around to seeing why my Dynaco Pas 3 Tube pre-amp was not turning on, and it appears it's the PA11 transformer that has no voltage coming off the two lines that are soldered to the SDS Labs board on the underside. I did see 12 volts at the fuse on the SDS card. Any...

Hello all, I have a Luxman 5L15 in for service, but someone has already worked on it...and cut some wires, fiddled with this and that. A loose screw rolling around in the chassis. A mess. It has a hard short and has blown the main 5A fuse under the chassis. All other fuses are intact, including...

Recently my transformer died and my electronics guru is trying to replace it. Does anyone know where I can get a replacement or the specifications so he can match it to something that is currently available?

Hello dear DIY in HIFI, Everything is in the title, I'm looking for a power transformer for Philips Laboratories AH 578 to bring back to life my power amp. Sadly, I don't know anything about it and its specs. There is no information written on mine (the picture below is what I found on the...

I'm currently working on a sa-gx690. There is no power to this unit and from what I can deduce, it is the standby Transformer that has failed. The numbers that are stated on the Transformer are 1H5C1 C EA3. Below that, the numbers 2813501 C29B The part identification on the service manual is...

I have an SA100 with a shorted HV winding. Have been trying to find a place that will either rewind it or make a new one to spec. Contacted six vendors, one said they might be able to make me a new one for under $500. I gave them the dimensions and the winding voltages and application. They...