Mullard date codes. Brent Jessee lists factory codes and production codes.

Mullard date codes started making the shorter plates in about 2/59 so you get both short and long plate versions with the same factory/date codes over many mnoths. 112 [ Follow Ups] [ Post Followup] [ Thread: Display Email Next] [ Tubes Asylum] Posted by KIS on April 30, 2005 at 11:46:34. my best guess is these were either 1969, 1979, or 1971! Lol Dec 3, 2024 · Vintage One Mullard 12au7 ECC82 Long Date Code B7K #118 Square Getter Blackburn. Both have the seam. Used. 00 £23. Oct 12, 2020 · See the differences of EL34 tubes from 1950s - 1970s Philips production in Blackburn (Mullard), Eindhoven (Philips) and Hamburg (Valvo). Comment: One of the first GZ34 tubes made. Ends in 4d 23h. Tested and closely matched on Top of the Line Calibrated Hickok 580 Lab Grade Tester. The codes are written in two lines on standard tubes and in two rows on special tubes (as E88CC) on the glass close to the base. P is likely the factory code. I am not going to get into the perennial discussion of the sonic properties of the yellow print valves over the stock boring white print ones but instead discuss A DIFFERENT advantage the yellow has over the prosaic white. Regular price £22. 203. (Mullard supply) 8 Philips, Eindhoven. Although, EIA is a very reliable number to identify the manufacturer, it’s not very easy to find it and in some cases it is completely missing making it practically impossible to know who made a tube. , from the late '50s to the early'60s. Carrying good white print, it tests as excellent using my AVO Valve Characteristic Meter VCM163 with the following results: ECC81, MULLARD, OLD  · Mullard codes. 1961-63 Mitcham Plant Date Codes. Marked in white ink-Made in Germany,7-08 date code,and an electron symbol. ECC88, MULLARD, 6DJ8, , WHITE PRINT, BLACKBURN Oct 3, 2022 · The EL84s were replaced in late 1965 or later. Except the Mullard is subject to the limitations of its tube type: it lacks a deep, expansive soundscape as well as weight in the mid-and-lower-mid range, both hallmarks of the Jun 16, 2024 · I’m having a hard time figuring out the date on these Mullard IEC 12at7s. These will have different type codes Nov 18, 2014 · Now there are plenty of sources of information about date codes for the Mullards / Philips valves manufactured in Hendon, South Australia. Eastern block Germany would be my guess with Oct 8, 2024 · This code was used to designate various changes Mullard made in their tube designs, as well as acted as a date code. Some of our eagle eyed readers Dec 29, 2007 · I picked up a Dynaco PAS on ebay and was pleasantly surprised to find in it three Mullard Long Plates with square getters. Other Tubes. The letters AW or MW followed by a serial number represent, respectively, electrostatically and magnetically focused Mar 23, 2004 · The European code is also known as the Mullard Code" in Great Britain, is the most common, and what we will cover here. After ± 1968 Siemens used metal tags inside the tube on the getter support in which the code was stamped. Jun 12, 2017 · MULLARD MAGIC MULLARD TUBES MULLARD VALVES VINTAGE RADIO MILITARY RADIO LEAK QUAD RADFORD U52 GZ34 KT66 PX4 WS19 MCR1 SPY SET R1155. Only wirewound resistors have date temp out Pair Mullard E182CC NON-USA made by Philips Heerlen ECC99 (V291/292) JG-5814A (12AU7WA) pair by General Electric, same date code, NOS v166/170 12AX7A, Toshiba, 14mm Long Plate , 1J Date Code, ECC83 On offer today we have a Toshiba white print 12AX7A made in Japan plant and carrying a 1J date code . physics group. 5U4G, Mullard, Amerty, CV575 U52 Black 3 Rib Plate EL34 Mullard Xf3 branded Valvo same date code V293 296 € 345,00 Add to basket; EL34 Tesla Welded plates O-O getter brown base same prod code NIB V50 v51 Sale! € 325,00 Original price was: €325,00. Most all Early electronic stuff will have a manufacturers code signifying who made it. Scott. Oct 29, 2024 · EL34/6CA7 Mullard made XF1 date code, hole in centering pin, large dark brown Micanol base, RARE. I assume where you asked where they were made, you meant plant? The date codes will tell you that at bottom. These are Mullard valves (mostly radio/TV) that I found really cheap. Private-brand tubes generally used a shippingdate code of two or three characters. That 12AX7 tube was made in 1960, and it's probably an I61 because it looks like a short plate with copper grid Jun 12, 2017 · The second part of the alpha code identifies the factory that manufactured the device, the most commonly seen codes and their corresponding manufacturers are:- A Mullard, Blackburn, pre Jan 1951 A Thorn, Tottenham, pre April 1964 AB Sylvania-Thorn, Enfield AC Brimar - Thorn-AEI, Footscray AD Brimar - Thorn-AEI , Rochester B Edison Swan, Baldock MULLARD MAGIC MULLARD TUBES MULLARD VALVES VINTAGE RADIO MILITARY RADIO LEAK QUAD RADFORD U52 GZ34 KT66 PX4 WS19 MCR1 SPY SET R1155. 00 £45. Date Oct 12, 2020 · (Valvo Amperex Mullard) Logos and Labels. my best guess is these were either 1969, 1979, or 1971! Lol Jul 7, 2009 · Anyone good with the mullard date codes? For the last 6 months I've been trying to organize my tubes so it's easy to locate what I'm looking for. Characteristics. Thomas Organ Vox dealers. Big Dicfoot, Oct 13, 2024 #5. There is much conflicting fokelore on the internet about the Mullard etched valve codes so I thought I would add our two penny-worth. The Manufacturer code is always the first symbol on the second line. I know that the 1022 is the IEC designation. See the entry for serial number 4347, below. Although the this Xf2 EL34 with halo-getter and welded plate is labeled as Valvo, in reality it is produced by Mullard in the Blackburn production site. - serial number 10317 (a Twin, Burndept-made chassis); Oct 4, 2018 · Personally, the best 12AU7 I’ve heard is the Mullard long-plate (date code: K61)—its tone and balance just seem so right, much like the Tung-Sol round-plate 6SN7GT. Brimar-made valves have a date code followed by a "part" code. GZ34. Radio valve lab. Carrying Apr 27, 2009 · This date code appears stamped on a metal plate, inside the tube, attached to the getter frame. Condition: Used Used. MULLARD MAGIC MULLARD TUBES MULLARD VALVES VINTAGE RADIO MILITARY RADIO LEAK QUAD RADFORD U52 GZ34 KT66 PX4 WS19 MCR1 SPY SET R1155. They have the vertical EMI logo and Mullard Electronics Sep 24, 2005 · Generally (and I can't express that enough) a Mullard or Philips vacuum tube will be marked near the base with a 2 row code, the first row is the manufacturers type code and Sep 26, 2017 · KT66, KT88) date codes prior to 1969 were two digits using letters = year, month. 3. *(There was actually a very short production run "Yellow Label" Mullard ECC83 produced right before this tube. Jun 23, 2003 · That code is the same as that allowed by UK military in their standard K1001 (from 1964). € 225,00 Current price is: Perfect matched pair of vintage Mullard E88CC/01 audio tubes - Made in Blackburn, Gt. Sep 6, 2018 #12 MULLARD MAGIC MULLARD TUBES MULLARD VALVES VINTAGE RADIO MILITARY RADIO LEAK QUAD RADFORD U52 GZ34 KT66 PX4 WS19 MCR1 SPY SET R1155. Apr 30, 2019 · MULLARD MAGIC MULLARD TUBES MULLARD VALVES VINTAGE RADIO MILITARY RADIO LEAK QUAD RADFORD U52 GZ34 KT66 PX4 WS19 MCR1 SPY SET R1155. When I boxed these, which was at least 10-15 years ago I Sep 24, 2005 · Generally (and I can't express that enough) a Mullard or Philips vacuum tube will be marked near the base with a 2 row code, the first row is the manufacturers type code and the second row is a country/date code. Jan 30, 2010 · 2- EL84's. In progress. The EL34 is a transmitting beam tetrode. Nov 11, 2012 · glass, along with the 'B' Blackburn Code + two Numbers and one Letter. And I would assume the 911 is the date. Hitachi, Japan 7 Electrical and Musical Industries. k. May 27, 2004 · Date codes are valuable in determining where and when the tube was made. Britain - 1960 - Gold Pins + Shield logo - Same date code - Ultra Rare Tubes Summary The "Super Mullard" is here! E88CC/01 (a. The Mullard's do have the B in the code. However, I've not been able to find any information about the valves produced in Ashfield, NSW by AWA. Posted by STEVE M on Apr 23, 2019. Brimar codes work in a different way. 6l6gb, sylvania, matched pair, green base print, back 3 rib plate, l5m, h5m date codes, 1957 manufacture Mullard Magic: For All Your Vintage Valve and Radio Needs! Sign in or Create an Account ECC81, MULLARD, OLD SHIELD, WHITE PRINT, FACTORY CODE, Tk3 B1J5, BLACKBURN 1961 MANUFACTURE On offer today is a lovely Mullard ECC81, a premium quality ECC81 carrying the date code for 1961. 5U4G, PHILCO ,5 RIB ,CHARCOAL ANODE, 5P DATE CODE, M-R PRINT, 1955 PRODUCTION This Philco tall form ST envelope 5U4G valve shows excellent bright getter and tests as EXCELLENT using my AVO VCM163 valve tester. Apr 27, 2018 · IEC imported Mullard tubes in the US, those are 70's vintage boxes, the 1022-319 means Mullard manufacturing made them, in 1973. Well, we did Mullard last week so this time, lets look at the Brimar type and date codes, oft seen on valve envelopes in minuscule inked print, but what do they mean? Brimar codes come in Sep 15, 2015 · WE – ASM Ltd, Broadstone ( ASM was a joint venture between Mullard and GEC, and the code WE really designates a GEC factory that pre-dated ASM) More examples of Factory Identification Codes can be found here. 12AX7 was allegedly introduced in 1948 stateside. It is clear from at least four surviving AC30s that Canadian-made Mullard EL84s were sometimes fitted at factory in early 1964. The item may have some signs of cosmetic wear, but is fully operational and Sep 5, 2018 · Date codes stamped or painted on means very early Euro. Top. 00. Since the date codes indicate Blackburn built tubes I'm sure you have real Mullards. Used tested good, white box. Posted by STEVE M on May 06, 2019. HOME Welcome & About Us;  · Mullard date coding (deciphere needed!) Post by Wallace » Thu Jun 21, 2007 5:15 pm I've found a GZ34 and I'm trying (without much luck!) to understand the date codes on it. Usually labelled Mullard, Valvo logos are rarer. Can someone tell me all the numbers out there and what they all mean? thanks. Xf1 coding indicates Mullards made in the Blackburn Works, in the U. Xf2 indicates either the Blackburn Works in the U. Common Labels Label Colors. 00 £28. Detailed description. Oct 20, 2017 · My erstwhile inquisitor was referring of course to the type numbers, screen printed with printers ink on a valve envelope - what do they mean? Well, let's start with what is commonly termed 'The Mullard System' and here is a nice little table to help you to decipher what the alphanumeric type codes mean, enjoy:- I can hear some of you exclaiming 'Oho, but what All we are concerned with here is the Manufacturer code. Feb 21, 2022 · Mullard date codes. f Standard telephones and Cables Ltd. Code: rsB 54. The last digit which represents the week of the month didn't start until about 1962. Measurement after 10 minutes stabilization. Brent Jessee lists factory codes and production codes. 1022 = Fisher branded Mullard/Telefunken/Amperex; 1109 Oct 12, 2020 · (Valvo Amperex Mullard) Logos and Labels. Thanks in advance! Jun 14, 2011 · 1955 5K1s, and there we have the earlier (Mullard-only) numeric type code 1324! I think that's 1324 A0. The white print Mullards all have the same date "B5F3" = Blackburn factory (B), 3rd week (3) of June (F), 1965 (5). HOME Welcome & About Us; MULLARD, I61 B1A, THREE FIGURE DATE CODE, BLACKBURN MANUFACTURED, JANUARY 1961 MULLARD, I61 B1A, THREE FIGURE DATE CODE, BLACKBURN MANUFACTURED, JANUARY 1961 Mullard Magic: For All Your Vintage Valve and Radio Needs! Sign in or Create an Account. 6V6GT, BRIMAR, FAT BASE, ORANGE BASE PRINT, BLACK GLASS, CV511, VT-107A, 6V6. + Philips, Sittard afd 22126 P La Radiotechnique, Clichy (Neotron) \ Amperex Electronic Corp. May 27, 2021 · I have a number of tubes that I cannot identify because the main print has warn off, but I can see the manufacture valve ID and date codes. But FYI, IEC wasn't above a bit of chicanery - many IEC tubes in very Mullard-like boxes were actually Russian. b1k2. Bulk-packed (OEM) tubes also carried an "E"; Jun 21, 2024 · Just because it may be a Blackburn Mullard doesn't gaurantee its any good. Etched lettering-has a KM4,and below that zero with a dot in it,then 5K. There is a current listing on an auction site that shows tubes acid etched "CØ 2≠ 7F" as being "1960's date code Siemens-Halske E81CC Triple-MICA tubes. Early XF1 date code (1957) "fat base" type, dual ring getters, good getter flash. Jun 12, 2017 · The JAN code is of course the US Military Joint Army Navy coding introduced in 1942 in which the code for a particular valve type comprises of an alphanumeric code, for example VT-114 and additionally a three digit alpha code. Mullard had quite a few factories plus the Philips Holland locations. Posted by STEVE M on Apr 30, 2019. An example of a rare Mullard 12AX7 code is: Mc1. Wrinkle Glass Halo Getter. The system is set out on the excellent tubemaze site. Factory codes USA date codes & manufacturer codes. This as been useful for identifying dates MULLARD VALVE ETCHED CODES - HOW TO INTERPRET THEM – MULLARD MAGIC Oct 9, 2024 · Pairs have *Heerlen Holland Production Date Code Gf9 42I2 or 4213 (first letter 4xxxx, 4=delta or left triangle for Heerlen Plant). , New York % Philips Apr 2, 2023 · I’m having a hard time figuring out the date on these Mullard IEC 12at7s. HOME Welcome & About Us; Apr 3, 2012 · However, European tubes don’t have EIA codes and instead used Date Codes. " &#X1F44D 1. The Mullard EF86. Osram Valve Co. Subscriber. The ECC82 (Brimar) 1960s. Different double getter (DD ring OO), base (metal big bakkelite brom or black base) or ECC88, RFT, WHITE GENERIC PRINT, IK DATE CODE As you can see from the test results we have excellent emission from each triode section within the envelope and superb intra section matching. Brimar date codes. sort of the same way you can identify a Mullard tube's MINT NOS 1961-1963 Mullard E88CC Type _01 AKA CV2493 special select low noise E88CC and CV2492 both Military Grade. Im not to sure you have the real thing. Mullard Magic: For All Your Vintage Valve and Radio Needs! Sign in or Create an Account. Then, a Mullard 12AX7 tube that wasn't very well washed down and also had a Sylvania EIA code AND a GE EIA code on it. See examples of different engineering codes and date codes for various Mullard valves. Some examples include: Oct 17, 2007 · UPDATE: One astute customer has informed me that GE offered 6681 tubes with the typical top seams, date codes, and "Gt. Regular price £45. The manufacturing factory code is a little more incomplete and uncertain, if indeed it is for a particular factory. K. See examples of Mullard factory codes, year and month codes, and engineering change codes. Since "b" is the code for Mullard, made in Blackburn 19% z 1938 T 1940 R 1942 S 1944 H 1937 U 1939 x 1941 Y 1943 K 1945 V On Government tubes, the "E" was printed separately, typically below the date code. Could someone out there in AK land Jul 14, 2020 · The code consists of multiple sections and usually look like: 4G9/980 (4th week of production in July of 1959, tube type 6060) BTW, if Brimar labeled tube doesn’t have the date code or it has foreign stamped on the tube, it’s not produced by Brimar, but by some other manufacturer. (The most common exception would be tubes like Apr 23, 2019 · THE GREAT MULLARD MAGIC BLOG — mullard etched date codes MULLARD VALVE ETCHED CODES - HOW TO INTERPRET THEM. , or Eindhoven, Holland tube factory (after Philips Electronics bought Mullard in the '60s). Description. Very rare. Britain" marking that indicates English Mullard manufacture. These also have Great Britain stamped on them. zaphod777 Senior Member Posts: 405. Cart 0. Scroll down: Mullard, Philips, and Valvo Tube Codes . 00 MULLARD MAGIC MULLARD TUBES MULLARD VALVES VINTAGE RADIO MILITARY RADIO LEAK QUAD RADFORD U52 GZ34 KT66 PX4 WS19 MCR1 SPY SET R1155. 1965 - US valve equivalents. First letter L - Luftwaffe (German Air Force) Second letter B - Cathode ray tubeD - Decametric wavesF - Special typeG - Rectifier or diodeK - StabiliserM - MagnetronS - Transmitting, wavelengths > 1 MV - Amplifier, wavelengths ECC81, MULLARD, OLD SHIELD, WHITE PRINT, FACTORY CODE, Tk3 B1J5, BLACKBURN 1961 MANUFACTURE On offer today is a lovely Mullard ECC81, a premium quality ECC81 carrying the date code for 1961. Post by Devon8822 » Tue Mar 20, 2007 5:16 am Cans omeone tell me what the number like 161 and 163 mean? I knwo they tell you the date and where they were made. The etched codes have value to us today as they contain two discrete nuggets of information May 6, 2019 · MORE ON MULLARD DATE CODES - THE YELLOW PRINT VALVES. Mullard in Australia also used a straight 3 digit number code that was a 2 digit year code with the month being last - YYM - but this Jun 2, 2005 · Page 4 4. Average brand new Philips and Mullard model equivalents (Based on the NZVRS lists with date corrections based on the Mullard codes and advertising evidence - red models were imported from the UK, models from 1940 were manufactured in New Zealand, no models were produced from the last part of 1942 until mid-1945 as factories were engaged in war work) Dec 3, 2013 · This kind of 4 code Mullard date code normally use before 1955, for example 1593 code is ecc82 before 1955 K61 code, I search you link too state the earliest type is 1954, but mine with 1582 J2 date code state it was made in otorber 1952! Photo of the date code, posted on December 3, 2013 at 20:41:33: S54B32 Jun 12, 2017 · LUFTWAFFE These German Eigantum der RLM valves carry an alphanumeric code in the sequence: two letters, one number. Apr 23, 2019 · Learn how to identify the origin, date and revision of Mullard tubes from the codes etched on the glass envelope. Comment. Post Cancel. An item that has been used previously. In forty years of collecting, I have only seen or heard about two handfuls of welded plate 12AX7/ECC83s with tall plates. HOME Welcome & About Us; 6l6gb, sylvania, matched pair, green base print, back 3 rib plate, l5m, h5m date codes, 1957 manufacture Mullard Magic: For All Your Vintage Valve and Radio Needs! Sign in or Create an Account Mullard Magic: For All Your Vintage Valve and Radio Needs! Sign in or Create an Account. Understand Codes. HOME Welcome & About Us; Mullard Magic stocks vintage radio, military radio like R1155, T1154, WS19, military spare parts, valves, tubes by GEC Brimar Mullard ECC83 KT66 ECC32 u52, radio components early wireless, vintage radio, domestic vintage radio, old technology of all kinds Anode current (Ia) is tested with the Telefunken/Philips/Mullard test setup: Va = 100V, Vg = 9 V in conjunction with a 680 Ohm cathode resistor. A NOS/NIB black base EL34 tubes made in the Mullard factory in Blackburn, United kingdom. EL84. Dswankey Lunatic Member. Dec 29, 2023 #6 There is much conflicting fokelore on the internet about the Mullard etched valve codes so I thought I would add our two penny-worth. MylesBAstor Dec 27, 2015 · Page 5 7 Philips, Eindhoven Radio valve lab. The black base is tight to the envelope and carries a yellow printed legend . 6 mA/V, the follwing results were obtained: NOS / Matched Pair Mullard CV181 / ECC32 Vacuum Tubes Same 1952 Date 4 X 6n8s Mega RARE 1578 Audiophile Version 60's 6h8s Metal Base Hole Plate NOS Pcs E88CC 6922 Old Tesla 1970's Audiophile Dual Triode Tube NOS Tested Mullard Date codes Q. Some of our eagle eyed readers Jul 3, 2013 · 1022 is the manufacturer code for Mullard/EIC. Comment: Quite rare. The final four numbers denote the date of manufacture of the device. HOME Welcome & About Us; Dec 29, 2023 · So the 136 and 1022 must be date/plant codes? Reactions: Mr Boochie. Carrying good white May 8, 2020 · MORE ON MULLARD DATE CODES - THE YELLOW PRINT VALVES. The Mullard receiving valve code system is described here and the transmitting and industrial code scheme can be found here. I haven't seen any date codes that contradict this but again wild guess. HOME Welcome & About Us;  · Just wondering if there is a chart for looking up date codes on nos mullard mustard caps so I can figure out the year of manufacture and for matching.  · Feb 27, 2014 · For the most European tubes made after 1955 date Jun 2, 2005 · Most Philips valves are marked with a group of symbols which contain coded information relating to the type, place of manufacture or country of origin in the case of bought Sep 24, 2018 · Philips / Amperex / Mullard / Valvo two digit codes Code Type Comment Code Type Comment Code Type Comment AC AW43-89 BX XL36 C5 E288CC AD EC88 BY Nov 30, 2008 · Would 60's Mullard AX7 tubes be black or dark gray plates? I have broken the code on my Mullard EL34 tubes. These are codes often seen stamped on components found in Apr 30, 2019 · THE GREAT MULLARD MAGIC BLOG — brimar date code BRIMAR VALVE TYPE & DATE CODES - HOW TO INTERPRET THEM. 0V against a nominal specification of anode current Ia = 1. The valves themselves are labelled AWV and have date codes etched in their glass. 2 mA and mutual conductance gm = 1. The ECC82 (Mullard) Vibravox, AC30/4 and AC30/6. 1 bid. To begin with the latter: MULLARD, I61 B1A, THREE FIGURE DATE CODE, BLACKBURN MANUFACTURED, JANUARY 1961 MULLARD, I61 B1A, THREE FIGURE DATE CODE, BLACKBURN MANUFACTURED, JANUARY 1961 Mullard Magic: For All Your Vintage Valve and Radio Needs! Sign in or Create an Account. EL34. Other code info is sometimes found on the tube in varying formats such as plant made in or date. Blackburn Mullard factory made. Many Brimar labeled tubes are actually Soviet made. Metro JTM45, Metro 50W Lead, JTM50 Black Flag Dec 1, 2009 · IEC was International Electronic Components, the importer for Mullard and other overseas sourced tubes. Regular price £23. EF86. a CV2493) Oct 3, 2022 · The Welwyn date code "TL" (= November 1962) on the cathode bias resistor of an AC30 from early 1963 visible in the mirror. An initial letter (A through L, including I) gives month, followed by the last digit of year. These used but tested good tubes have repaired centering pins on the base, and the tubes are good as new! 6j5g, raytheon, sc122a, matched pair with same date code, orange base print, envelope cartouche, june 1942 production, new, boxed Mullard Magic: For All Your Vintage Valve and Radio Needs! Sign in or Create an Account May 29, 2024 · Mullard Code. Apr 23, 2019 · Learn how to interpret the Mullard valve etched codes that contain the valve type, production site, year, month and week of manufacture. The etched codes have value to us today as they Feb 1, 2022 · There is much conflicting fokelore on the internet about the Mullard etched valve codes so I thought I would add our two penny-worth. AC30s with original valves. receiving valve technology group. Date code interpretation - 2 or 3 character code (pre 1960) / 4 character code (post 1960) Lastly, there are differences on the different versions of the ECC35/33 on the physical structure and etched code: Nov 30, 2008 · B0G is a legit date code on a Mullard. ECC81. B901 (well I Oct 12, 2020 · EL84s from Mullard production are very stable and show high emission (>50mA) even after many hours of use and looking pretty used. From 1969: YYWW The year 1945 started A at A for 1945, andJanuary the months started A at May 29, 2024 · Modern Mullard voltage stabiliser tubes have codes commencing with the burning voltage (e. Anyway, the date code on all three is the same and is: mC1 B71. 2 days ago · 6SN7GT 6SN7 6SN7GTA 6SN7GTB B65 6F8G VT231 BL63 VR102 6H8C ECC33 12SN7GT 12SN7GTA, BRIMAR, Mullard, Pre Amps Tubes, RCA, Tube By Brand GZ34 Brimar Mullard date code B2E3 /B8K1 Amplitrex AT1000 Tested 1 Match Pair $ 199. Others I found online are 1324 B1, B3, C3, D3, E2, E4, I2, J1, J2, J8, K9, L9. Printed on the side is GZ34, Great Britain 33. JULY 1961 DATE CODE. 6V6GT, BRIMAR, FAT BASE, WHITE BASE PRINT, Dec 5, 2024 · The old-style Mullard date code (for the manufacture of the valve) had only three elements - letter-number-letter. Sep 16, 2010 · I once found a 1959 Blackburn produced Mullard GZ34/5AR4 initially faintly labeled two years later with 'Amperex', then washed and relabled with the new shield logo sometime after October 1968 (with the 1959 date code!!). . glass group 9 Philips, Heerlen Radio valve lab. ) CV4004 M187 ECC83 Box plate: The CV4004 box plate Mullard is a military production tube that can be identified by its unique plate structure. Jeff West's best estimate is: Shaw was "P" Perivale was "ZB" Hammersmith was "Z" but nothing certain for the "4". I thought I'd gotten all of my better tubes organized and that all the boxes of tubes left to go through in storage were just the common ones. There is also a "4" stamped inside the glass on the bottom of the tube (where the diamond would be if it was a Telefunken), and the inner shield is grey, not shiny. Identified by: - No hole in guiding pin - one closed getter - no plate holes - Straight plate sides. 00 £22. Read and understand the codes . KM 4 05K (kinda like this) They test a solid 100% and only drift down 2% on the 'life'test. I tried to get a photo of the date code but this is the best I could do. Code stamped is 1022-911. . I will deal with the former in more detail later, but the alpha code is a manufacturer code. The first pair of numbers denote the year of manufacture and the Apr 23, 2019 · THE GREAT MULLARD MAGIC BLOG — valve date codes MULLARD VALVE ETCHED CODES - HOW TO INTERPRET THEM. aculco (432) 100% positive; Seller's other items Seller's other items; Contact seller; US $39. 40. mullard etched date codes; mullard expandabox; mullard film; MULLARD HIGH SPEED VALVE TESTER; mullard high speed valve teste; mullard high speed valve tester; mullard lighter; Mullard describe the E88CC as being for use in cascode circuits and as a multivibrator and cathode follower in computers. Instituut voor Fysisch Onderzoek E Hyperlec Brive (Correza) F La Radiotechnique, Suresnes f Marconi . The power rating of the resistor is marked as being 4-5 watts. tubeactive AK Subscriber. 150B2). Maybe the first EL84 made by Mullard : Code: kM1 BXXX Blackburn kM2 B7XX (also found) Identified by: - 1 (round) hole in plate. For instance, F91 is a long plate 12AX7 variation, and the F92 long plate eventually replaced the F91 and so on. 33P would be 3rd quarter 1973, etc. Search. 128. Mullard UK was painstakingly detailed about Blackburn codes. The Mullard method of coding valves is also being used by some other ECC81, MULLARD, OLD SHIELD, YELLOW PRINT, FACTORY CODE, Tk3 B4D1, BLACKBURN 1964 MANUFACTURE On offer today is a lovely Mullard ECC81, a premium quality ECC81 carrying the date code for 1961. CV2492, MIL SPEC E88CC, MULLARD, GOLD PIN , WHITE PRINT, MITCHAM MARCH 1963 MANUFACTURE, E88CC. The special quality in this case referred to its long service life and not, as normal, to its being a ruggedised version. For Va = 250 V Vg = -2. (later Thorn) East German origin (after 1 Jan 1970) rX2 B2J5 = rX > EL84, 2 > change_code 2, B > Blackburn Mullard, 2J5 > 1962 October 5th week. The etched codes have value to us today as they contain two Jul 23, 2021 · Mullard changed its designation code on ECC35/33 from 1347/1324 to RU*/5K*, somewhere in 1955 3. ECC82 ECC83 E88CC. Vox AC30/4. Factory symbols A Wiener Radio Werke “WIRAG”, Wien B Mullard, Blackburn C Hendon Works, Alberton, Australia D Valvo, Hamburg d Ned. g. EZ80/81. Indeed, some GE 12AX7 and 7025 tubes from the 1970s were also Mullard made, so they must have made some 6681s for GE as well. HOME MILITARY, VT-107B , 2G DATE CODE. People collect tubes based off this code frequently as it is a way to follow the history of the Mullard 12AX7. Thus A0 = Jan 1950. Those suggest to me that we are looking at an MY-format date code where A = Jan and L = Dec, and years range from 1948 to 1954. The ECC82 (Amperex sheets) The ECC83 (Mullard) 1957-1968. Note: Siemens never used week codes. Regular price £28. Tube has a halo getter. plznel oxwiu eqmtan jwttfa vwdrq laq hixr irrnqtk alq tzyrnuwv