Triplett 3444 tube analyzer,digital plate current meter,usedTriplett 3444 tube analyzer, digital plate current meter, tester for 6c33c FAACondition: it is test gear, in excellent condition, it has been cosmetically restored to it's original condition, less a very few minor blemishes. This analyzer is so nice you could set it in you...2295.00

Triplett 3444 tube analyzer, digital plate current meter, tester for 6c33c FAA [Expired]


no longer for sale

Condition: it is test gear, in excellent condition, it has been cosmetically restored to it's original condition, less a very few minor blemishes.   This analyzer is so nice you could set it in your living room! This was an FAA technician's designed analyzer, with tag ( see photo). Only a few 3444 were made with this case.

Please examine all photos, including examples of tubes on my 3444 with is electrically identical to this offering.

Measure transconductance/gm and match plate current with high repeatable precision. An opportunity to verify what you buy or sell, or keep tabs on your tube and amplifier investments with total confidence and no guessing.

Triplett 3444 Tube Tester/Analyzer -  Total Rebuild with military/industry grade parts selected for low ESR and low current leakage capacitors, as well as precise values for all parts including resistors, 120 hour burn-in minimum, cosmetically refurbished & electrically calibrated to the original master assembly model, not some guestimate, or the guide found on the web.  New signal and meter tubes, plus independently powered and regulated plate current meter included so there is no parasitic interference with the gm measurement.

12 month warranty on parts installed.

This is a worry free tester and analyzer.  Even IF you amplifier has 'auto bias' you still need to know the health of your tubes since they are at the very heart of your investment, and auto bias will not detect leakage or shorts, or tell you if a tube is near worn out. Can you match those preamp tubes for both gm and current?  If you have a moving coil cartridge, this is really important.

Read dual element tubes such as a 12ax7 or 6sn7 with the flip of one switch.

You can test a large number of tubes for plate current above 50am. A stock 3444 can not read these tubes. 

If you need a tester which can test and analyze a KT88, KT120 and KT150, 300b, 6L6GC, EL34, 6550, 7591A, 6c33c, 6sn7, 12ax7, 12au7, and many hundreds of others. This is One of the finest tube analyzers ever made.  A Stock 3444 can not read these tubes for plate current accurately or any above 50ma, this one, with the custom DATEL digital current meter, can.   If you are familiar with a 'plate curve chart', you can plot your tubes using this tester or create new tubes setting from scratch.

This rebuild and calibration is good for a minimum 10,000 hours of actual in-service testing use before any 'check-up' should even be considered, that is about 20 years for most users. Your tubes are tested in class 1A conditions as per tube manufacturers data plate curve references, no Hickok or TV7 can come close. 


After the sale help on testing by phone or email, especially for 6c33c tubes (adapter is required for this tube and is not included, but we can make one).  We are there years after you buy to help you if you have a question on need tube settings, or help, on a tube you never had before. Check the feedback or ask past buyers.

The 3444 was Preferred over Hickok testers by the Navy, Air Force, FCC, FAA, radio and TV stations, commercial air lines, and more. One of the Best Tube Tester Analyzers ever Produced in the U.S.A.

Will not test high power transmitter triodes such as the 845 or 211.

Analyzer details:

Direct Gm Readout From 0 to 30,000 Micromhos on clearly marked scales, each scale is calibrated to 0.5% or less full scale.

Read dual element tubes such as a 12ax7 or 6sn7 with the flip of one switch.

Replaceable socket savers for the octal, 9 and 7 pin sockets (above bias dial, under the cover)

Vishay balanced bridge rectified and capacitor filtered Plate & Five Filtered Screen Voltages from 12 to 250 VDC, Hickok has no filtering on any model.

Bias Voltages; 0-5 and 0-50 VDC fully adjustable and filtered to 0.5% accurate.

Plate Current Readout on automatic independent digital meter up to 199.9ma for precise tube matching.

Leakage Readout on Main Meter; 0-20 Mega ohms, not just some simple short detection as most testers such as Hickok have.  This is of major importance to protect your equipment. A one million-ohm leakage on the screen can damage your amp very quickly and Hickok will miss that (752/539/580 exception) until it reaches 250 thousand ohms leakage which is near a short level. By then you can have something burned out.

Gm Meter isolated From direct Gm circuitry by Its own micro-ammeter 12au7 circuit. Hickok is not isolated.

Gm Circuitry calibration on-the-fly by a simple push of a button, It is Self Check Feature for most accurate readouts. Hickok must be sent to a facility for this recalibration.

Four fixed Grid Signals 33, 100, 333, 1000 Millivolts AC Measures to less than 0.5% error., at 5,000 Hz (independent tube circuit generated).

23  selectable AC Filament Voltages

Tested Under Voltages Encountered in Real Life Applications and at manufacturers 1A data points.  Hickok at 150vdc drops to about 122 with a common 6L6GC or EL34, any KT type even lower.

Tests Most Old and New Tubes with highest and repeatable accuracy.  Easy to create new tube data settings.

Sockets for 4,5,6,7 Pin tubes as a combined socket, Octal, Loctal, 7 and 9 Pin Miniature, 7 and 8 Pin Subminiature, 5-Pin Nuvistor

Built-In 9 Pin Straightener

Noise Test Jacks

Illuminated Main Gm Meter and Roll Chart

DC Overload Warning Lamp


Copy of Operating Manual included, plus our quick and easy testing methods primer.

Shipping to verified addresses only if using a credit card or Paypal. Checks accepted. Shipping will be determined after the sale, and will include insurance and sign for, and packing materials.  Paypal or card fees split 50/50.


Most all Testers Sold including eBay are questionable, make no mistake about that, require a $400-600 rebuild and Calibration, and many times higher bills for a total rebuild which this analyzer has received. None offer a digital current meter for matching tubes.


We are known as c.g.industries, in business since 1973.

[email protected]