Germanium transistor tester. Tested for gain and leakage with a Peak DCA55 tester.

Germanium transistor tester Transistor Tester will waiting for user input at the end of a test. Do you have to remove a transistor to test it? While removing a transistor from the circuit is ideal for accurate testing, it is not always required. Big bullet casing, and cool vintage vibe. . classic transistors represent the best of 1960s germanium PNP alloy junction technology and were the basis for RCA dominance in early commercial transistor audio products, including guitar amps and fuzz tones, hi-fi amplifiers and transistor The transistors have been selected and checked with an Atlas DCA55 tester to determine gain (Hfe) and leakage (Icb) – Separately, these rare NPN Ge Transistors will cost you well over $40, and these are selected for gain and low leakage! ***Please note that the picture shows the tester and a bunch of transistors while sorting. Switching time will be reviewed at a later time. With germanium’s I usually ballpark with this then do ordering / matching the old school way on a breadboard / test box. This is a germanium transistor tester. Tools & Supplies. So not impossibly high, but improbable enough to suggest that the transistor tester may not have accounted for leakage. Germanium fuzz's seem to have a special place, (tonewise), in guitarist hearts. Oct 1, 2012 · http://www. Crude test, doesn't always work, but sometimes it does. com Considering the above are correct hfe values then everything but the hfe 23 will work well (depending on leakage and the circuit used in). Bought GT308V, GT403B, GT321V and MP20A's. The tiny legs are the reason. 7V which makes it hard to distinguish germanium from silicon diodes. The small bear and RG keen testers are good. Sep 26, 2024 · Bipolar junction transistors were the ones we started using long back for our hobby electronics projects. With NPN and PNP transistors the common-emitter current gain factor and emitter threshold voltage from the emitter leakage current are measured. Another component tester that you could use as your transistor tester is Bside ESRO2 Pro. I picked out two with high gain (hfe = 105 and 120) and low leakage (~100 ua). Jul 17, 2022 · Hey all, Joe from Gray Bench Electronics here. Also germanium are more sensitive to heat than silicon and can end up in thermal runaway and destroy themselves. In the early 2000s, Cornell made a Fuzz Face variant called the First Fuzz . Sep 6, 2019 · Most datasheets of germanium diodes specify Vf at 0. This is the base open test. I made a slight change to put the switch on the board with leads for the DMM. Great option for Q2 position of a Fuzz Face, or anywhere a higher gain, low leakage Ge transistor is required. Aug 10, 2020 · I finally broke down and bought a Peak Atlas DCA55, and it's now my go-to for transistor, diode and LED testing. 8 inch Colorful Display: LCR Meters - Amazon. 5V-Transistor Detect Area: 0. This ability is changing electronics, pushing low-power transistor technology forward. Once the pedal hacker community had the geofex gain/leakage tester, they went wild with specifying gains and leakages on new nuggets of germanium they found. It does not do things like leakage tests but it will give you an BK Precision 520B - Industrial Transistor Tester. These are a great Germanium transistor that are more stable and lower noise than most Germaniums. I got the layout here. 2m resistor, and ideally a a 2. All of those are germanium PNP transistors and the datasheets say their gain is 70+. Take it easy! Aug 11, 2017 · The main difference between germanium and silicon transistors in switching circuits, be they either PNP or NPN transistors is that VBE for small germanium is about 0. However, it will then search for all other device types and configurations. ), and Sep 11, 2014 · For a germanium transistor you'll read between 2 and (at most) 4 volts, for silicon it would be between 5 and 7 volts. Adjusting the variable resistor will cause the NPN LED to light up indicating that the base current is flowing. Guitar pedals are notoriously okay with being imprecise. At this point I’ve managed to collect a relatively tidy little supply of germanium transistors from numerous sources, some are pulls from old radios and the like, some purchased NOS, representing Japan, Russia, the US and a believe a few from China, running from the 1950s through modern NTE make. You can use the diode test function on a multimeter to determine the polarity. Bside ESR02 PRO Digital Transistor Tester for SMD Transistors. New Old Stock GT402 (ГТ402) USSR/Soviet Transistor. 7 volts. The only NPN transistors you are likely to encounter are in transformerless output stages. Measuring the gain was mainly an issue with germanium transistors, where the gain was more likely to change (e. I built the transistor tester described here and it appears to function as expected (ie readings seem appropriate for what one would expect) however on 2 of these transistors (so far), the reading at all points and switch position was the full 9v supply. Mar 9, 2020 · That being said, many lower gain transistors will sound great, I don't follow the recommended "gains". Too high and the ohmic drops in the Ge Dec 8, 2024 · Germanium transistors can operate at just 0. Because I absolutely hate math I had put together a spread sheet with the formulas ready to go! GT402 PNP Germanium Transistor. ) Apr 27, 2021 · See “Figure 12: LTSpice simulation of oscilloscope / arbitrary waveform generator NPN transistor hFE test circuit” above for details. It's based on this article by R. If the leakage current of the germanium transistor is quite high (due to warming from your fingers for example), the DCA75 can reject the "correct" pinout. Connect appropriate polarity to the collector ,from the emitter run through the current function of a DVM before going back to supply. Sep 26, 2024 · I understand you well. Sep 4, 2024 · For an open transistor, check the same terminals; if the multimeter shows infinite resistance (or out of range) in all directions, the transistor is likely open. You’ll either need to use a transistor/component tester or build a small Ge transistor tester to measure the gain (hfe) & leakage of each transistor. Or buy a tested set of fuzz face transistors from pedalhacker or smallbear if you want it to be right the first time. I've used these successfully for over a decade in Germanium and hybrid fuzz peda Page 6 4. Besides testing transistors, it can also test normal diodes and Zener diodes, thyristors, and components like resistors, capacitors and inductors. If the leakage current of the germanium transistor is quite high (due to warming from your fingers for example), the DCA55 can reject the "correct" pinout. Buy a bunch of the same transistor because you will find a wide range of gain values in a batch. Actually, correction: the cheapest and most accurate transistor tester is the one you can build on a breadboard with 2-3 parts. Also I just replaced the NKT275 with BC109 (NPN) switched the battery and the circuit worked fine, but when I go back to the germanium transistors no dice Dec 7, 2022 · Denis Cornell was a builder and tester of original Fuzz Face pedals made by Dallas Arbiter. You should either be paying more for a matched set (see small bear), or buying a big lot (at less per piece) to test and match your own. May 29, 2020 · “cheap component testers” What is a cheap component tester? The term “cheap component tester” is meant to cover any one of many models of small semiconductor analyzers based on microcontrollers like the ATmega128 and which run software designed to run a bunch of tests on a connected electronic component, guess the type of that component (e. That was my first germanium fuzz build and I still use it to this day! It's also what got me started on collecting germanium transistors and now I have 300 or so. Germanium’s unique features are revolutionizing the semiconductor industry. Just pulled the trigger on a ADS1115 module from Adafruit (preassembled ADC circuit for these kinds of projects). I recently used this new method to test a pack of (10) MJ15022 output transistors. I am also interested in methods and devices for testing transistors. Jun 7, 2024 · Thanks @crutschow. In the TME catalogue, set the "transistor test" filter in the "portable digital multimeters" product category. We then obtain a list of those models that allow you to perform a transistor test, both using classical probes and using special pin sockets that work with pnp and npn transistors. In those days we had PNP type of germanium transistors and NPN type of silicon transistors. The AC126 is a higher gain transistor originally used for audio preamps and could be used in Rangemasters, Tone Benders, Fuzz Faces, etc. Look at your schematic. Previous topic - Next topic. one graph of an AC128 with Ft at 1 MHz around Ic Apr 18, 2015 · In addition the modern silicon transistors usually have a pretty stable gain. I tried it with a 1N5819 and that works just as well. In these cases, one needs to refer to the manufacturer’s pinout information, or try the transistor in-circuit to verify its pinout and functionality. Jul 26, 2019 · A priori, cet électrophone utilisait des transistors germanium type AC117P et AC175P, dans l’étage de puissance. 20 Any idea of brand or any explanation of its origin? AVO TT169 Transistor Tester Vintage Test Sep 17, 2018 · CORRECTION to the video: on 2. At a higher current Vf is expected to be around 0. 2M resistor and 2. 2V, far below silicon’s 0. synthrotek. 7V. To test them, just reverse the battery polarity and the meter leads in the tester diagram. Feb 7, 2017 · Build a supply about half the Vceo. Some things I've noticed in testing all my vintage germanium, vintage silicon, and modern silicon transistors:-NPN Ge transistors are more often available at lower gain when Transistor Tester is powered. I saw a post on DIY Stompboxes where someone else was attempting to do this, but I never saw them complete it All transistors are painstakingly tested for gain and leakage using a Pro Atlas DCA55 test unit and then marked and sorted. I have measurements for over 600 germanium transistors in my records, and 461 would be the second highest hFE measurement. It explains pretty much everything going on in this process. An AC128 on the TC-1 reads 320uA leakage and 142 gain Ever hear about "leaky" germanium transistor and wonder how to measure that? Well, here's a little utility board that allows you to test germanium transistors. Jul 31, 2015 · Following on from the Transistor / Component Tester review and teardown video, I briefly introduce germanium transistors and see if they can also be tested w Oct 10, 2021 · But for basic purposes and for the transistor tester it works OK - depending on what grade of precision you're looking for. MP26A = GC112. May 30, 2022 · I'm looking to buy a Multi-function Tester - TC1 it looks very good, I want to know about germanium transistor leakage, is its accuracy good in this regard? Note: I don't have the money to buy peak atlas. If you’re just testing a handful of transistors, breadboarding RG’s circuit is probably the faster way to go. Diode/Transistor Tester – Assembled & Tested – DT100. However, we can cook up a device to test germaniums and figure out which ones will still work in our retro-fuzz. A little heat from your fingers will throw the readings off. Jan 28, 2020 · I got my bag of resistors from overseas - measured with my transistor "tester". However, like the 1N34A, most of those germanium substitutions are also obsolete. The output of Q2 is feedback in phase to the base of the test transistor causing Jun 1, 2023 · Saved searches Use saved searches to filter your results more quickly Germanium Joe's Fuzz Face Transistor Kits!This kit includes ten hand selected and tested germanium transistors, grouped into sets for use in a fuzz face style circuit. The test transistor in this circuit is an NPN. Dec 28, 2015 · In another forum concerning vintage electronics I have been told The Sencore TR-139 transistor tester does a very good job of evaluating Germanium Transistors. The AF117 is a high frequency transistor often used in FM radios, would probably make a great Rangemaster. The AF11x problem But of course we're firmly in the past with germanium. Buying germanium for $6-$10/piece is almost always a bad idea. It will pick out the base of an unmarked transistor. Yes, in certain types of germanium (eastern european and russian especially), leakage is harder to come by. Jan 4, 2025 · Then, If I remove that good transistor from slot #3, and place that QP-6 good transistor over into slot #4, leaving slot #3 now open, I get clear and loud sound out of the left channel, with low and muffled sound out of the right channel, so by process of elimination, it appears that nothing else is damaged in the internal circuitry. 47k resistance with some resistors in serial (plus a snappy little momentary push button for doing the switch to 2. I noted down the values for one transistor, the first voltage was 2. Jan 16, 2021 · TRANSISTORS: RG Keen, Germanium Transistor Test Method If you haven't heard of this before (which seems unlikely), here's the original RG Keen article , which explains how it works. Tests Germanium Transistor for Gain and Leakage - information VERY useful for Stompbox Builders! Aug 20, 2015 · I have a transistor tester on my DMM but without leakage measurement. Keen, which you should definitely read. If you can get 2. Most early transistor radios use PNP transistors. Probador de transistores multifuncional para detección automática de transistores NPN y PNP, FET, diodos, diodo dual, tiristor, SCR, identificación automática del pinout del transistor. I use a spreadsheet set up with the calculations ready to go for testing; there's also an online calculator here . You should test your transistors and make note of the transistor gain (hfe). I'm finally getting around to testing them and set up the RG Keen germanium test circuit on my breadboard, with the 2. I've heard at least one of the transistors in a bender needs some amount of leakage. When Transistor Tester is powered, a Short time press of the RPEWS will switch on the Transistor Tester, and start a Test. They are equivalent to AC128, but with better voltage ratting in the datasheet. 3 Test a PNP transistor It shows that the DUT is a PNP transistor, the test terminals 1, 2 and 3 are connected to Aug 9, 2024 · I recently purchased a pre-matched pair of germanium transistors from Smallbear for a Fuzz Face (their "Continental" set) and found something that seems odd about one of them: the included specs for Q1 indicates that a white dot on the body denotes the collector but, on my multimeter transistor tester, that leg is showing to be the emitter Jun 22, 2021 · Make sure you wait for the transistor to cool off for a few minutes after you connected it to the tester. My EE knowledge is a bit shaky, wanted to know if anyone see any obvious problems Thanks in advance! The best transistor tester that I and other field professionals recommend is either the M328 transistor tester, or the TC1 component tester, or the BSIDE ESR02 pro. EDFM’s Transistor Tester is a budget friendly manual means to test transistors for their leakage and gain values. In each fuzz face kit, you will find transistors from a variety of manufacturer A germanium transistor sound test of the transistors supplied by Pedalhacker:AC125k | AC128 | CV5416 | ASX12D | GT2308 | GT308BLink to Pedalhackers Ebay Stor Nov 3, 2023 · 3. I haven't done any frequency/bandwidth testing yet. I am primarily working with vintage germanium transistors and vintage capacitors, so I can sort through a particularly large lot of vintage components to test and verify what is still usable and what isn’t. stompboxelectronics. The BK Precision model 520B Transistor Tester is designed for in-circuit and out-of circuit transistor testing with special features for making additional tests on devices out-of circuit. I saw a post on DIY Stompboxes where someone else was attempting to do this, but I never saw them complete it Apr 25, 2023 · For some types of transistors (JFETs, NPN germanium transistors, for example) it is difficult or not possible for the pinouts to be accurately determined. Jul 19, 2024 · Figure 2: The Digilent Analog Discovery with Transistor Tester (sold separately) is used to characterize a BAT46 diode. Aug 2, 2020 · How to determine leakages and gains with Germanium Transistors, and how to improve upon them by using Sziklai Pairs. Feb 23, 2022 · There are four basic tests required for transistors in practical troubleshooting: gain, leakage, breakdown, and switching time. Features: Diode Mode: Checks all types of diodes – germanium, silicon, power, light emitting (LEDs), and The Collector and Emitter of my germanium transistor is showing the wrong way round, is the DCA55 wrong? A. 1 day ago · NPN Transistor, connect C to B then to Anode on test circuit, and E to Cathode on test ckt PNP Transistor, connect C to B then to Cathode on test circuit, and E to Anode on test ckt The trick is to use the right amount of current. Others have posted ballpark ranges. I have a multi unit that does a limited amount of testing now but would like to get a better unit. I'll definitely socket and play with them, but what has everyone used before? These are measurements I got: TG5S = OC71 Germanium PNP ID hFE Vf #1 75 146 #2 64 143 #3 77 147 #4 31 Hey I just had a quick question regarding germanium transistors and measuring their leakage. 2M, which is nifty), plus a voltage divider to get my source voltage as close as possible to 9V. 2 Test a NPN transistor It shows that the DUT is NPN transistor, test terminal 1,2,and 3 are connected to E,C and B pins, Gain is 248, and forward voltage on junction B and E is 619Mv, leakage current ICE0=0,ICES=0. One thing I do know, is that at least for now, there is a whole lot of real high quality Soviet germaniums on eBay that you can use in place of the expensive OC and AC types. May 7, 2018 · I've got a stash of NPN germaniums (2N1304), and I built RG's germanium transistor tester to sort out the gains. capacitance values, inductance, and the quality of diodes and transistor junctions. 5 leakage 0. a long time press or Rotation of left and right the RPEWS will enter the function menu. I used a 2k and 470R in series to get as close to 2. Q. Transistor Capacitor Tester: FNIRSI LCR-P1 transistor tester can be used for the measurement and analysis of patch component, NPN, PNP, triode, MOS, field effect transistor (FET), diode, Zener diode, capacitor, resistor, inductor, battery, etc Oct 6, 2021 · Quote from: Kevin Mitchell on October 06, 2021, 11:51:52 PM I got lazy. For Ge transistors, it will give you NPN/PNP, identify CBE leads, Hfe with test current used, Vbe with test current used, and leakage (critical for Ge transistors. des. The ASY25 and ASY48 is a switching transistor, might work well in a Fuzz Face. transistors type mfr. So you can go to eBay & buy 20-30 transistors & test them yourself, and if you're lucky you'll have 3 in the ranges you need. User actions About this item . 3 volts whilst those of silicon are about 0. appl. BJT Transistors are effectively two diodes back to back. You have -22V on the "east" side of R134, probably -20V on C117. 47k that's good enough I think - I used a 2. Elenco DT100. The output of the test transistor is fed to amplifiers Q2 and Q3. I found a bunch of non matched transistors of the same model that I was thinking of buying as the price for 100 is the same as 3 matched. I saw a post on DIY Stompboxes where someone else was attempting to do this, but I never saw them complete it I knew one of the problems was that the ADC on the ATMEGA328P is kind of limited and prone to too much noise So I found a breakout board for the ADS1115 16-Bit ADC that was available and Jun 23, 2010 · You need a fresh 9v battery, a 2. 2M resistor to the base, and turn on an LED while it's connected. org, le schéma est lisible ! IL y a eu plusieurs versions de ce tourne-disque. Admittedly, it is difficult to test SMD transistors using test leads or slots. 01-30V-Capacitance: 25pF-100,000uF I use a cheap atmega based component tester that I'll guess is very similar, and it's perfectly fine for transistors assuming you're just trying to get hfe and pinout. Aug 13, 2013 · A germanium transistor that tests over 250 for hfe on a regular tester like on a cheap DMM is certainly leaky, and will sound crappy in any distortion circuit, especially the FF. Mar 15, 2017 · My small component tester recognizes the devices as Ge, but some of the readings it is spitting out are crazy. I built the RG germanium tester to test them. 7 uA). PNP Germanium. L’étage de puissance fait appel à des transistors complémentaires PNP & NPN. a Short time press of the RPEWS will switch on the Transistor Tester, and start a Test. Jul 30, 2024 · The germanium transistor gain tool lets you simplify the process of calculating the hfe for germanium Fuzz Face circuits. It can also test batteries, even though that didn’t work very well for me. He then turns on the transistor by connecting base to collector with an alligator clip. My 328 component tester gives the wrong VF around 600mV (instead of 180-200mV) for a bunch of 2SB56's I have lying around, reporting hFE from 130-530. For example: At V CE of 5 V and 4th I B curve (representing I B = 27. Donc, il ne peut pas utiliser 4 transistors PNP AD152 ! Sur RadioMuseum. 2n21 we pt cont sw 2n80 cbs gpnp gp, lf, audio 2n139 rca, sylgpnp hf, if amp Sep 25, 2020 · Buy AITRIP LCR-TC1 Colorful Display Pocketable Multifunctional TFT Backlight Transistor Tester for Diode Triode Capacitor Resistor Transistor LCR ESR NPN PNP MOSFET with 1. Some data that I've seen suggests that some Ge devices have low gain at high frequencies, especially at low Ic (e. This tester automatically detects if a NPN/PNP transistor, FET, diode, dual diode, thyristor or SCR is connected and has an automatic identification of the pinout of the components. Apr 27, 2024 · Can anyone recommend a transistor tester that would work for germanium transistor's? I was looking at the DCA-75 but those seem to be out of stock everywhere. 47k exact. Never used/ NOS/ New Old Stock/ MP26A transistors pnp germanium alloy versatile more bass. Geofex's handy circuit can test both, so that's the way to go for me. One of the unpleasant problems with transistors and diodes is leakage. Cheap transistor testers aren't that accurate, even the ones that show leakage. These are the best because they come from reputed brands, are high quality, tested by a lot of people and these people are happy with them, reliable, and yet come with decent price Jan 14, 2009 · PIC - based Germanium Transistor Tester? Started by polaris26, January 14, 2009, 02:19:36 PM. That said, it actually is pretty consistent with transistor tests. It is a veroboard layout of the tester I read about on geofx. Home; Products ; RF Bipolar Transistors NPN Silicn Germanium RF Transistor BFR 740L3RH E6327; Infineon Technologies; 1: $0. An easy, albeit more expensive option, is to go buy from a shop that will pre-test the transistors. You can buy our transistors in Sep 28, 2011 · And it turns out that virtually all germanium transistors are electronically 'leaky' over time, and the majority are no longer usable. I add a 4pdt to switch from PNP to NPN, as well as a DPDT to add the 2. Mar 31, 2023 · If you google "2SB54 transistor" you usually get a datasheet link pretty high in the results. Switches: p-n-p/OFF/n-p-n, 100uA/500uA/external, leakage/Hfe. Go Down Pages 1. 5 out of 5 stars 18 Test & Measurement. Today I saw an answer about what device measures and takes into account leakage in germanium transistors. 3. so subbing silicon into a circuit for a germanium fuzz and getting it to work will not give you something that sounds different. The gain number isn’t that important, most Ges test around 100 (unless they are leaky). Costs about the same as a decent multimeter and worth it. But UK and american transistors, especially from the 50s, leak heavily. Arduino IDE C code for the Arduino Uno, using a SSD1306 OLED display and an ADS1115 16-Bit ADC. G. It's true that silicon transistors are better in most regards, but used appropriately, germanium transistors can give excellent results, and generally, they are remarkably reliable - especially when you consider how young the semiconductor industry was - but there are some noteable exceptions. Germanium Transistor In Order of Case Style, * T C = +63°C, ** T C = +25°C. there is an interesting fuzz design I built recently that uses four silicon transistors to aim for a germanium fuzz sound. It features an in-circuit testing and polarity indicators for both transistors and diodes. And although it may sound weird, I was toying with the idea of making a Germanium Fuzz, where the transistor was actually mounted inside a tiny environmental chamber. resistor, capacitor, transistor, etc. Testing from base to emitter and/or base to collector, the direction of the diodes will tell you whether the transistors are PNP are NPN (they're almost definitely PNP). They should be germanium if you want to get the classic 60's/70's "soft" distortion. simulating RG's transistor tester), theis model gives 60 uA of leakage and gain in the high 40s. Among germanium transistors, many type numbers (see the list below) are possible candidates for FF circuits and clones. And so can you! I had breadboarded the germanium leakage and true gain tester from Geofex as I finally decided to order boxes of those recently popular new-old-stock Russian germanium transistors. There are electronic engineers in the Zenith Transoceanic world who have done so in the Royal 1000, and 3000 radios and they tell us the result is not worth the PIA it is to do the mod' remember these Zenith radios do not use printed circuit boards it is only Mar 9, 2017 · I've measured the same transistor (Russian P29A germanium transistor), and what I've got: Small Bear Jig I've build it in 1590DD enclosure with two milliampermeters and external banana sockets for external multimeter connection (DC, mA). The instrument is designed for a minimum amount of control manipulation, making for rapid testing of most It probably takes an hour to test 50 transistors now that I have the tester build as a physical device. If you reverse the leads, you should not get a reading. 14 I say “we have here the Silicon transistor” but of course I mean: “The Germanium transistor” (!), also when explaining that Sep 7, 2009 · For "normal" conditions (e. 472k as possible (I got to 2. When it comes to building guitar effects pedals, there are two main types of transistors that we use. 6V when adjusting the trimpot for Q3? Hello! I have built the (Fuzzdog) Tone Bender Pro MKII and it works and sounds good on first test with guitar, however, when it comes to biasing the transistors, the collector voltage ranges I see when adjusting the trimpots for Q2 and Q3 do not match those in the instructions. A Fuzz Factory would also be a fun project, and if you have any particularly leaky ones you could build a Dizzy Tone Note the schematic diagram on page 6. Click on the Part Number for Pricing. Though many of the later First Fuzz pedals use rebranded NKT275s made by a different manufacturer, the early versions of First Fuzzes used genuine Newmarket NKT275 transistors To figure out what type of transistor you have, you should always find the corresponding datasheet online. Transistor Tester will be waiting for user input at the end of a test. A great little multi-function component tester! Drop the component and hit start and it will automatically recognize the type of component and give a few measurements. Like Hfe as high as 360, when according to the data sheet it should be 34/115. Click on the for Detailed Specifications. lts base current Ig is therefore add up to the voltage drop along the collector resistor is hpg x lg x R2. Additionally, DCA75 test currents are completely independent of battery condition. This is a circa 1970 instrument. The main technical characteristics of the transistor MP26A: The structure of the transistor: pnp• Pk max- Constant power dissipation Collector: 200 mW; fh21b- Cut-off Mar 13, 2010 · At 25C, Icbo for a germanium transistor, whose power dissipation is the range of some hundreds of milliwatts, is of the order of microamperes. But on the other hand, I don't like dual Russian tranny's, maybe in q2 but a Amer/ euro/ Japan/ tranny in q1. Bought them off eBay from a Romanian seller, knowing i'd take a risk to get a bag of lemons. Jun 18, 2019 · FNIRSI LCR-P1 Transistor Tester, Mosfet Transistor Capacitor Tester, SMD Electronic Component Tester, Diode Triode Zener Diode Resistance Inductance Battery Test LCR Meter MOS PNP NPN ESR Meter 4. 2k and a 270r resistor in series to get 2. You may have heard that there actually exist NPN germaniums. What determines how a transistor can be used & in what circuits is the gain (hfe) & leakage current measurements of each individual transistor. 469k). This unit was mainly design for germanium and other high leakage junction transistors but works with all junction transistors. Today the Hfe measurement is more like a function test and verification to have the right pin-out. comHow to Test Germanium Transistors - We use these AC128 transistors in our Fuzz Face Clone Pedal Kit. The transistors have been selected and checked with an Atlas DCA55 tester to determine gain (Hfe) and leakage (Icb) – Separately, these rare NPN Ge Transistors will cost you well over $30, and these are selected for proper gain and low leakage! ***Please note that the picture shows the tester and a bunch of transistors while sorting. In this video we'll discuss the ins and outs of testing and selecting germanium transistors for use in guitar p Arduino IDE C code for the Arduino Uno, using a SSD1306 OLED display and an ADS1115 16-Bit ADC. Swapping and experimentation is highly encouraged. Gain and leakage are tested with DMM. 59V and when I push the button it was the same, nothing changed. Ube = Vbe = base-emitter voltage at the indicated collector current. Tested for gain and leakage with a Peak DCA55 tester. You should be able to buy trannies with a range of 60-90 hfe for Q1 & Q2, and maybe 90-120 for Q3. During a end of test ,and before it’s auto switch off. as already mentioned, transistors are temperature-sensitive and germanium most of all. g. Feb 8, 2017 · Don't bother to try and modify a circuit using Germanium transistors to use silicon transistors it requires a redesign of the circuit. May 9, 2021 · it is the type of transistor that is mostly giving the character to the fuzz box. A long time press or Rotation of left and right the RPEWS will enter the function menu. May 8, 2014 · TEWA Germanium Transistors from Poland are great !!! ASY34, ASY35 and ASY36 are PNP Germanium transistors made by an extinct polish company called TEWA, I bought a pair of each of them from an old worker that I met in the Wolumen street market. So, anything plastic molded will be silicon. base-emitter diode of a BU508D transistor often goes unrecognized due to an internally parallel-connected 42Ω resistor, making it impossible to test the transistor function. Apply voltage (not very long) see what the current is. When testing NPN germanium transistors the polarity should be reversed for each test, then the results will be the same. com FREE DELIVERY possible on eligible purchases May 7, 2024 · An hFE of 461 is really high for a germanium transistor. I used a AA119 for the diode, but you can also use a Schottky Diode if you don't have a Germanium one. Forward current transfer ratio, or gain, is the main thing to find out. Silicon transistors and germanium Dec 15, 2021 · How to test a transistor with a multimeter from TME offer. the exact opposite of all this would happen with an NPN transistor. -Self test with automatic calibration-1/8" color display-Diode Range: less than 4. It separates germanium from silicon diodes, indicates the polarity of such diodes and separates germanium from silicon transistors and NPN from PNP types. As the picture displays, the base current of the transistor under check moves through R1. 1mA which the tester doesn't support. In this video, we'll demonstrate how to use an Arduino Nano, an OLED Display, and a 16-Bit ADC to tell if our Germanium Transistor is an NPN or PNP, how much // voltage, as this is an NPN transistor, we must subtract from the rail voltage to get leak // voltage leak_milliVolts = rail_milliVolts - collector_milliVolts; An Arduino-based, ProMini Germanium Transistor Tester. Germanium transistor tester questions Apr 25, 2023 · For some types of transistors (JFETs, NPN germanium transistors, for example) it is difficult or not possible for the pinouts to be accurately determined. Then I built a mock up gain stage on the breadboard to make sure these would bias correctly. 200uA of leakage is not that uncommon. (see photo below for pinout) Q2 will be MP21D (МП21Д) PNP: with hFE between (90-110) for the Q2 position. with time or heat) and parts were scattering more. Further research suggests this may be due to the tester getting thrown by voltage leakage, which Ge transistors are known for. 01-4. Jul 1, 2018 · At :45 seconds into the video, this gentleman begins to use the 4M ohm setting of a DMM to apply voltage to the transistor, across the collector/emitter junction. 4. The Collector and Emitter of my germanium transistor is showing the wrong way round, is the DCA75 wrong? A. You'll see Iceo continue to drop as the transistor cools down. Simulate the PNP transistor test circuit in LTSpice… The PNP circuit is the same as the NPN transistor test circuit. Aug 11, 2012 · I'm lazy and use a Peak DCA55 to measure transistors which will automatically give you the leakage reading for germanium with the added advantage of identifying the pins for you so you don't even have to refer to the datasheet. It is more noticeable in germanium transistors than in silicon ones. Solder sockets into your transistor pads and swap them out until you find the sound you’re after. Mar 17, 2020 · If a germanium transistor is generating noise, sometimes holding a hot tip soldering iron very close to the body of the transistor, will cause the noise to vary within the transistor. I also test for AC beta as some identical "reading" transistors from different makers, are way apart when it comes to AC gains. Print. High-power Darlington transistors, which also have base-emitter resistors, can likewise be difficult to identify, It's true that silicon transistors are better in most regards, but used appropriately, germanium transistors can give excellent results, and generally, they are remarkably reliable - especially when you consider how young the semiconductor industry was - but there are some noteable exceptions. Jun 18, 2017 · TUT is the Transistor Under Test, TUN stands for Transistor Universal NPN, TUP is Transistor Universal PNP and DUG stands for Diode Universal Germanium. Aug 31, 2024 · A'ite: Am I correct here in presuming that the cheapie amazon/aliexpress TC-1 multi-function tester is essentially useless for testing germanium transistors? Some it seems to do OK on, some it's just likeway off vs the RG Keen method. También se puede utilizar como señal cuadrada, generador de señal PWM I need something that can test transistors for gain and leakage as well as measure capacitors for capacitance and leakage. Jan 10, 2018 · Additionally more the measuring becomes self-governing of the supply voltage of the tester. 5V-Zener Diode Detect Area: 0. Ten NOS British Military CV7355 2N1309 Germanium transistors. Apr 28, 2014 · I am sure the 'experts' use their vastly superior Atlas tester but I highly recommend making something like this if you aim to test any decent amount of germanium: You can watch the transistor fluctuate and/or settle which gives you indications on the device's quality that an Atlas cannot. The AF11x problem Oct 7, 2021 · I had breadboarded the germanium leakage and true gain tester from Geofex as I finally decided to order boxes of those recently popular new-old-stock Russian germanium transistors. Under similar conditions a silicon transistor has an Icbo in the range of nanoamperes. You will receive the following set: Q1 will be MP21D (МП21Д) PNP: with hFE between (70-89) for the Q1 position. While most germanium transistors are PNP, there are some NPNs, and they do make good Fuzz Face clones. Down you get the leakage, and up you can get the gain. Breakdown, or knee in curve traces are tested with a semiconductor analyzer. put a 47k resistor in series with it. Sep 30, 2020 · If your transistor has no shorts and just really low hFE=8 then I would say it's faded due to old age, and not whiskers- or your tester might never have seen germanium before. type mfr. What are the consideration for selecting a 1N34A substitution for a crystal radio? There are many alternatives to the 1N34A. Jul 1, 2024 · TL:DR: Tone Bender Pro MKII - Why can I only achieve a range of 0-3. 85; Jul 27, 2023 · It’s obviously a germanium transistor with a hFE 99. 472k resistor but I wouldn't drive yourself mad aiming for ideals (especially when dealing with germanium transistors). It also will do in circuit testing. Jun 9, 2014 · Without load on the speaker terminals, it is normal to have a high negative voltage. What makes this choice interesting is its SMD socket. Jan 7, 2025 · I've found a few germanium transistors in old 70s radios, and a lot of germ diodes like 1N60s in old 8 track decks. I’m entirely new to the germanium realm, but I have collected a handful for experimentation. This tester seems to like to read older ones around 1-5 Hfe, but the rest of the numbers are normal. Now germanium transistors are seldom seen and we have both NPN and PNP types of silicon transistors. Mar 11, 2020 · What you want to do is go on eBay or something and get a bag of 20 or so PNP Germanium transistors. Feb 5, 2018 · Germanium semiconductors in molded plastic cases are an ABSOLUTE exception (only one I am aware of is the AF279 HF transistor), since most germanium parts were made in processes that require the part to be kept in a clean, hermetically sealed case (which plastic molding does not reliably provide). However again with germs don’t worry about the Hfe so much as the iceo when dealing with NOS or salvaged ones. This is normal for a germanium transistor but if you have this with a silicon transistor, it is a defective silicon transistor or a "pre-biased" silicon transistor. Measure leakage and get about 20uA 4 days ago · The Fnirsi LCR-P1 is a small transistor tester full of surprises. I'm making a more permanent version of RG Keen's germanium transistor tester. During the end of test, and before it’s auto switch off. MA909, MA910 Germanium transistor 70V USSR Lot of 100 pcs New. "I'm not sure, but I believe the parameter you want is Iceo. Nov 3, 2017 · I've bough a load of different NOS germanium transistors to see what the hype is all about. Dec 15, 2021 · How to test a transistor with a multimeter from TME offer. A Spaceman Sputnik II. Oct 8, 2021 · If you have a batch of germanium transistors, how do you tell which are going to sound good and which will not? To a first order, you can just gain select them in a DMM that has a transistor checking range. TIA « Jul 31, 2023 · For a npn germanium transistor, the transistor will turn on when the positive probe is connected to the collector and the negative probe on the emitter. Silicon has been used, and many people like the harsher clipping, but it is a different sound. DT-100 is a fully assembled and tested dynamic diode/transistor tester kit. This will not only tell you what type of transistor it is, but also the assignment of the pins. Do types of germanium transistors really matter? I just bought some matched Mp40a Russian transistors which sound great in a mk3 tone bender. aefewe khe hysmlt nrr hsdzrc qmvakk ssgfus mlbqkm oqf gtlji