Monday, September 16, 2019

Sound Technology 1500A Tape Recorder Test System Part II

This guy has been interesting. A computer of sorts from 1980. Removed all the boards and started replacing tantalum capacitors one by one. Once the big values were replaced each board came to life and finally the screen came on. The voltages also were correct.  Next step is calibration and try to pass the self test..

Sunday, September 15, 2019

RIP Ric Ocasek

One of the coolest cats to walk the earth. The Cars certainly rounded out the 80's nicely.

Thanks for all the great tunes. 


Sex Machine Super Sex Version 
Gawd dang this band is hot.....

The opposite end of the spectrum... Flying Lizards trying to get on up... 

Perhaps my new favorite cover.. 

Friday, September 13, 2019

Retro Hi-Fi Girl Friday

Posting a late Hi-Fi Girl Friday in honor of Thomas and Bjorns new book  High Quality Horn Loudspeaker Systems.

Thursday, September 12, 2019

High-Quality Horn Loudspeaker Systems By Bjorn Kolbrek and Thomas Dunker

Thomas and Bjorn have just completed a major work on horn audio history. They have spent the last 14 or 15 years on this tome. I can't imagine the passion and dedication that went into this book. They literally spent years in research and writing. I hope to meet these gentlemen in person some day as it would be a priveledge.
They just annouced their website with information for the book. I am pleased to announce it will be available on amazon. I don't plug many things for money but please support their work by purchasing this book October 15th. Please reward their dedication and hardwork. Please buy a copy.

Wednesday, September 11, 2019

Monday, September 9, 2019

Sound Technologies ST1500A - Tape and LP Test System

Chris and have been working on this guy off and on for a while. There is finally light at the end of the tunnel.  Here is a pic of the ancient guts.

 With these boards removed we get all the correct voltages. Not so much when they are installed. I started replacing all the orange tantalum caps... Lots of caps.
This is what the input board does to the 1500A. Very sad. 

 Fortunately with the input board removed there are some signs of life.

 Can't belive how happy I was to see this boot up screen.. LOL.... Now back to replacing all the tantalum caps on that dam input board and hope it works.

Friday, September 6, 2019

Thursday, September 5, 2019


AMPEREX tubes are among my faves when it comes to the 12A family.

Tuesday, September 3, 2019

Friday, August 30, 2019

Thursday, August 29, 2019

Eimac 150T Advert

Tuesday, August 27, 2019

Yet Another 866A Video

This time a time lapse. Very strange not what I expected to see. I was surprised by the flicker rate because in our time they were solid blue. 

Monday, August 26, 2019

Monolithic Tube Power Supply Success!

Chris and I have been working on this power supply off and on for a year and a half. There is alot under the hood on this one. The previous power transformer failed but we had this beautiful Kenyon transfomer available. This power supply is stable and runs cool at 940v and 280ma.
 Of course the mercury vapors are 866A but the not so common tubes are the 6D22S which has a 30 second warm up.
 The blue glow is captivating and the westing house meters are stunning.

 I filmed our first startup here.

Now to build the other three chassis for this amplifier 8-)

Sunday, August 25, 2019

Freed MEGOHMMETER Test equipment.

My friend Chris brought over another piece of cool test equipment. This is not just an ohm meter but a MEGOHMMETER!!!!! Great googlie mooglie!! I've been honing my DIY skills repairing old test equipment. We have been through a stack of Sound Technology test gear. Next on the list may be a few old scopes. Not sure when we will get to this one but it sure is cool.

Friday, August 23, 2019

Wednesday, August 21, 2019

1931 Electrical Catalog Excerpts

 I dig the early audio catalogues.,

Monday, August 19, 2019

Friday, August 16, 2019

Thursday, August 15, 2019