The gate driver circuit shown in the screenshot uses BC547s, which are limited to less than 200 mA current. Instead, if the two transistors were BC337 or PN2222A which can easily handle over 500 mA, they could charge and discharge the gate faster, and thus reduce the dissipation in the MOSFET.
Archive for the ‘Transistors’ Category:
2024-02-17 BJT, FET Curve Tracer
This very comprehensive website has a transistor and FET Curve tracer. Also a simpler curve tracer for all components. Click on box to download the schematic, etc. https://www.changpuak.ch/electronics/Curve_Tracer_advanced.php#
2023-07-12 DC-DC Converters That Used Germanium Power Transistors
Me and my high school friend made a DC to DC converter that would give us 30 or so volts at a couple amps from a 12 volt battery. We used germanium power transistors which could not go much above 10 kHz. The Delco’s and the 2N458A’s were our favorites – we managed to push
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2023-06-06 ITT2222 Not Standard Pinout Of PN2222
Caroline Joy Barnhart Your Kit must’ve had those “high quality” Radio Scrap components. 😆 My guess is you got one of the ITT2222 transistors. They made their plastic packaged version of the 2N2222 so that it did *not* conform to the standard E B C of the PN2222 or MPS2222. They were unpopular because they
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2021-11-23 Replace Germanium With Silicon Transistors
I also remember those projects that used the CK722 and 2N107. The last few years I have been repairing older transistor radios with germanium transistors. I have had a few of them with bad germanium output transistors, and I’ve replaced them with silicon PNP transistors, along with a change in base bias resistors. They work
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2020-06-01 Motorola HEP Catalog Transistors pp 10-12
These are scans of the specifications for most of the Motorola HEP line of replacement transistors. Germanium and Silicon. Pages 10, 11, 12.
2019-01-15 Zenith Royal 200 Conversion to Silicon
I’m thinking of pulling up the end of the 100 ohm and looping the lead a few times through the ferrite bead. If that still doesn’t stop the ringing, I’m thinking about replacing the bead with an RF choke. Every time the ringing is reduced the reception gets better. I checked to see if I
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2020-01-08 Sorting Transistors Compared to Picking Fruit
I started thinking about how the makers of transistors sort the different grades of transistors as they’re manufactured. I thought that a reasonable analogy would be similar to how a farmer might sort the fruit he harvests. Here’s what I came up with.The farmer starts with the fruit his workers have gathered. The fruit is
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2018-08-24 2N3904 & 2N3906 for Output Transistors
From FB group Building Transistor Radios 2018-08-24 – The discussion was about the OTL complementary symmetry audio amplifier that Mr. Barnett has posted several times to the group, which uses a 2N3904 and 2N3906. Willie Barnett Let’s talk about current. Suppose your amp has a 9V supply. When the output transistor is turned fully on,
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2018-08-20 2N3904s From Mouser And Ebay
from FB group Building Transistor Radios 2018-08-22 Olek Kopyto I recently did some tests on 2N3904s I got from Mouser and from a Chinese eBay seller. The ones from Mouser had a current gain of right around 200, right in the middle of the 100 to 300 gain range according to the data sheet. The
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