TubeSound TTM-1 Tube Tester & Matcher
Meet the TubeSound TTM-1: Testing of almost all amplifying tubes (triode, tetrode, pentode, beam power) from antique 4-pin (such as a #10, #45, or #50) through 9-pin novar (such as a 7868). Socket...
View ArticleLimitations of cheap DPM’s and DMM’s
©2011, Bob Putnak. This post examines the performance (directly related to the input impedance) of low-cost meters; specifically, I explore a common multipurpose Colluck PM-128E DPM (digital panel...
View ArticlePluggers comic conjures ‘National Radio News’
For tube fans, today’s Pluggers comic strip conjures memories of the NATIONAL RADIO NEWS magazine cover, Aug-Sept 1945 issue. The Pluggers comic is in today’s newspaper July 23, 2011, or you can enjoy...
View Articlerare Rockola jukebox amp hum problem
I wanted to write about a unique problem in a Rockola model “O” jukebox amplifier (from a Rockola 1426 jukebox, vintage 1946). The amp is a very primitive design: class A, 4 tube operation consisting...
View ArticleTransformers can blow in the blink of an eye
Recently my longtime trusted Eico 1030 regulated high voltage DC power supply succumbed to a catastrophic failure — a shorted transformer winding. The power transformer has a separate winding that...
View ArticlePhase Linear …on the bench!
Something that I don’t see everyday… Phase Linear audiophile gear! In fact, this was my first opportunity to use, repair, and evaluate any Phase Linear gear. While I only use tube audio gear, it is...
View Article…more Phase Linear (round 2)
My neighbor was thrilled to find someone local who could repair has Phase Linear audiophile gear. One of his friends was also a Phase fan, and his gear had been sitting for a longtime in disrepair....
View ArticlePACO SA-50 Tube Amp Rebuild
I find it exciting to discover a nice audiophile amp from a nondescript brand. In this article, I chronicle my rebuilding of a PACO preamp-amplifier model SA-50. PACO is the Precision Apparatus...
View Articlethe Reprocessed Tube Racket
I found an interesting tube-related article in the Dec-1955-Jan-1956 issue of NATIONAL RADIO-TV NEWS. The article exposed a supply-chain problem during the 1950s where unscrupulous vendors would buy...
View Articlethe Crosley Auto Expressionator circuit
In the 1930s, Crosley designed a tone-volume expander circuit that would, in theory, add fidelity to the music that you were receiving from over-the-air radio AM transmitters. The circuit was said to...
View ArticleTV-7 micromhos conversion calculator
TV-7 tube tester micromhos calculator Meter: Range B Range C Range D Range E Range F µmhos DIRECTIONS: Enter your meter reading (0 – 120) into the “Meter” box. Choose your Range Switch position in the...
View Articlerepair broken TP-Link TD-8616 ADSL modem
If you are trying to fix a TP-Link TD-8616 modem, chances are good that this is your problem. On May 21, 2012, I purchased from Newegg a new TP-Link ADSL TD-8616 DSL modem to replace a very old Westell...
View ArticleVintage Advertising page
On this page, you will find PDF’s that I create from my own collection of vintage advertising for tube amps, speakers, test equipment, microphones, etc. The ads often provide production specs and...
View ArticleCBS Hytron 12BH7 letter about Hickok test
Here is a letter from the Technical Service department of CBS Hytron tube company, dated June 1954, that discusses a common problem with tube testers. In this letter [ PDF ], which I scanned and...
View ArticleQ&A regarding HP Officejet R-series repair
Q&A regarding HP Officejet R-series repair: Hi, I have your article on “Repairing HP Officejet R-series”. I used it several years ago; cleaning the mirror fixed the problem. I’ve lost flexible...
View ArticleQ&A regarding different micromhos scores
Hey Tubesound, Hoping you can answer a question for me. I have an Amplitrex and a TV-7D/U tube tester. The Amplitrex tests a 12ax7 as new at 1600GM. According to your TV7 GM calculator, I believe...
View ArticleFor sale 1976 ZENITH Bicentennial tube caddy
For sale 1976 ZENITH Bicentennial tube caddy Zenith released this tube caddy to celebrate the 200 year anniversary of the United States of America. Caddy is real nice condition with minor exception...
View Articleset 1 to 23 John F Rider Radio Perpetual Troubleshooters Manuals
FOR SALE: complete set — Volumes 1 thru 23 — of John F Rider Radio Perpetual Troubleshooters Manuals. That says it all. You get all 23 volumes, and YES obviously that includes individual Volumes...
View ArticleTV-7 micromhos conversion calculator
TV-7 tube tester micromhos calculator Meter: Range BRange CRange DRange ERange F µmhos DIRECTIONS: Enter your meter reading (0 – 120) into the “Meter” box. Choose your Range Switch position in the...
View ArticleEico 500v cap tester rebuilt-calibrated FOR SALE
Eico 950B high-voltage cap tester rebuilt and calibrated $239 free ship USA. See our page FOR SALE – TUBE TESTERS AND TEST EQUIPMENT. Link to that page is on the menu that you see on your left here.
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