Old School Tangential Tonearm : Rabco ST-4

After using in  fair condition for a long time. 

My Rabco ST-4 " Straight Line Tracking" turntable should be need a new plinth.

Highly recommend to use with  thick cantilever cartridge like Shure M3D/M7D 

and others in same era.

Also match with legendary Jazz & Blues.

Thanks http://wegavision.pytalhost.com/ for this rare catalog.

 

Monday Modify : Continue With NEC Mono-Block

From my previous post

http://mellowgroovy.blogspot.com/2014/03/the-lost-world-nippon-electric-company.html

It's time to start up new design amplifier project 

with original main parts of NEC Mono-Block. 

Winding Resistance Step Attenuator

After searching many information of vintage step attenuator 

for use in my tube preamplifier.

I've found attenuator in the box that use Tech Lab 600 Ohm attenuators.

Tech Lab Inc. was made high quality attenuator like Daven did,

that use in audio and measurement products like Western Electric, Tektronix, etc.

Stereo Sound Japan was provide information of 

Tech Lab PK-322 that has 2 types of resistor inside.

Type I : Mold Resistor & Winding Resistance Type

Type II : All Winding Resistance Type

Attenuator in the box from Stereo Sound Japan 

was use in many test system of Tube Kingdom magazine.

Like Stereo Sound Japan Website recommended.

Type I attenuator matched with all popular and modern music and 

Type II attenuator matched with old school music like Blues, Jazz and Classical. 

Both types improve dynamic and detail of sound system a lot. 

Let's try !!!

Tuesday Tube : P.A.-210A Perryman with Mesh Plate

210 tube series still one of the best DHT tube for Brass, Woodwind and String.
Especially Thoriated-Tungsten match with those instruments than Oxide-Coated.

But 210 tube with mesh plate can sing both vocal & instruments best together.
Deep, Airy and Detail are words that I can describe
after compare with other 210 tube series in my preamplifier.

210 mesh plate still hard to find
but worth to get for listen hidden sound from your system.

First picture is a pair of 210 Marathon with old style filament suspension.

The rest are pictures of 210A Perryman with ST-era style filament suspension.

 

The Lost World : Nippon Electric Company

I've pick these amplifiers from local second hand repository for a long time ago.

They've used in the theater somewhere before.

Output impedance are 200 ohm and 166 ohm,
so need line matching transformer for use with standard speaker too.

Nippon Electric "2154-H" 50 Watt Mono-Block Power Amplifier
using 807 tubes in Push-Pull configuration

drive by 6AU6 with separate rectifier for driving stage and power stage.
Many functions for check and test parameters. All components made in Japan.
Parts like capacitors, plastic knobs and wires seem deteriorate.

Connection points so dirty and iron parts had corrosion.
No any information about this on WWW.

Difficult to draw schematic for refurbish.

So ............ it's time to clean & change circuit with new parts and tubes.

Which tube should I go with? 

The Richman Game

The Wolf of Wall Street : 2013

About 3 hours in the theater that full of energy from all characters and story.

Contain many notable scenes and might be use in real life.

Sorry for DiCaprio who miss his 4th Academy Award but for this movie, 

Scorsese is the "Real Wolf".

Tuesday Tube : 4043C STC (Standard Telephones & Cables)

4043C/CV1448 is DHT tube that use the same filament specification (7.5V/1.25A)

as 10 series tube (10/10Y/210/801A/841/etc.).

Highest maximum plate dissipation rating 35W compare 10Y/VT-25 (12W) 

and 801A/VT-62 (20W).

Same UX-4 base like 10 series too. Black mono plate with ^^^ filament.

Very linear triode characteristic curve. 

Nice to make DIY project like Class A2 Single Ended Amplifier. 

Will get output power more than 6W !

Very linear curve !