Binson Echorec 2 ready for the road

A few days ago I was able to get done with the Echorec. Taking care of the pending steps, guided me to a really great session of enjoyment playing around with the Echorec.

The motor was taken apart, cleaned and rewired the cap and coils connections. That was pretty straight and let me confront the heads alignment process. This can be by far the hardest work to be done in a Binson Echorec. Being gently with the head friction while manipulating it and being able to fix it without loosing the working position is a time consuming process.

After placing the unit in its case and let it warm for a while, it was the right moment to test it for real. Expected oscillations being the best signal of the proper working of the Echorec, trimmer last adjustments even for the magic eye and time to record some files.



Nice and soft echo to play 3 Libras of APC. Forcing a little bit the echo lenght and gain we can obtain interesting effects closed to oscillating fun!

Antique radio!

A nice antique radio just arrived to be checked, repaired and restored if viable. It is a simple mono radio with volume, tuning and band selector controls.  The back plate is lost, but based in the guts I would say it was built sometime around the 40’s.

 It was a relief to see all the tubes where they are supposed to be, the rectifier UY41, the typical output pentode UL41, diode pentode UAF42, double triode UBC41 and the triode-hexode UCH42.  Although I cannot identify the model, based in the tubes and configuration we find the typical radio modules like detector, audio preamp etc

Is one of those devices designed and built when isolation from supply was not mandatory. That is why it has no power transformer and basically relies in supply voltage level and components impedance, basically five tubes, that is why this kind of radios are known as AA5. It was a way to save money in components and this design comes from the 30's. Back in those days this type radio was designed for 125Vac which is applied directly to the UY41 anode and the series connected heaters of all tubes. It is not a good idea to have a radio around, with this configuration and no back plate, it could be lethal!! Insulation trans and a back cover  is mandatory for this radio.

Components do not look too bad but already tested some of the caps and as expected they have aged, there is also some rusted nodes and degraded wires. Time to check main components and repair the unit.

Binson Echorec: Work Update!

Retaking the Binson restoration! Big steps have been taken and I hope to get done with it in a few days. Take a look at the recording unit before cleaning and properly greasing.

You can see old grease where the drum support fits to meet the internal ball gearing, the reading and recording heads, the magnets, the transmission wheel and the support for the missing spring. It took a while to clean every part, grease as needed, calibrate the spinning parts and build a new spring so the transmission wheel would have the proper friction with the magnetic drum.

The next step was reviewing the electronics and replacing wiring and components if needed. Most of resistors and caps in the signal path and tubes’ bias were replaced with quality components. I found some mods which made no sense, even some bridged resistors, as soon as I find out its purpose I will let you know the solution to this mystery.  Thankfully the wiring was not in a very bad condition which is a surprise in a Binson Echorec. One of the effects of time in this unit is some deterioration in the original LESA pots, but thankfully not enough to need replacing.

It was time to turn on the unit after all the electrical restoration included the power supply circuit. It was a good feeling to measure good readings in all the plates and bias voltages. Also checked the oscillator signal to make sure it was correct, getting a nice sinusoidal of nearly 52KHz.

It was the right moment to loose the right side plate and replace the Geloso connectors with ¼’’ female jacks. It is a good idea to use a solid support for the jacks, in this case two aluminum plates were mechanized to fit in the Binson’s plate and use new rivets to hold them in place.

I have now to rewire the front lighthning and replace the broken lamp holders, also the magic eye needs rewiring. Afterwards cleaning and adjusting the cap-motor deeply and the most consumming time operation, calibrating the recording unit. Lets speed it up!