I got my hands on a small lot of Acrian TT5021 RF power transistors. They are bipolar RF transistors in 7mm diameter white ceramic pucks...

I got my hands on a small lot of Acrian TT5021 RF power transistors. They are bipolar RF transistors in 7mm diameter white ceramic pucks (probably BeO) with four wings and a stud. They are probably roughly 30W VHF amplifier transistors. Does anyone have a datasheet for these things? Google came up dry. Thanks, Jeroen Belleman

I have a couple of simple 555 monostables, the first to delay the triggering of the...

I have a couple of simple 555 monostables, the first to delay the triggering of the second. https://www.dropbox.com/s/6uboy3fgd0ixhxa/GenerateNegPulse-1.jpg?raw=1 But I'm struggling to extract the brief -ve pulse required for the Main mono. I thought it would prove simple. But bread-boarding various combinations of R, C, diode and NPN or PNP transistor has so far not yielded a winning comb...

https://www.fabricatedknowledge.com/p/the-rising-tide-of-semiconductor I've also heard that the cost of one next-gen euv scanner is well...

https://www.fabricatedknowledge.com/p/the-rising-tide-of-semiconductor I've also heard that the cost of one next-gen euv scanner is well over $200M, and that the design and mask set for a high-end chip costs a billion dollars. We just don't need few-nm chips. -- Father Brown's figure remained quite dark and still; but in that instant he had lost his head. His head was always ...

Sometimes one needs to power a circuit from one source or another. Most LDOs, or indeed most normal regs, feed current back up to the source....

Sometimes one needs to power a circuit from one source or another. Most LDOs, or indeed most normal regs, feed current back up to the source. LDOs tend to use a PMOS pass transistor which has a parasitic diode. I am doing a design where I am using the Ricoh R1191 for this https://eu.mouser.com/ProductDetail/Ricoh-Electronic-Devices-Company/R1191N033B-TR-FE?qs=%2Fha2p yFaduhEV6ZG3xOqbaXpS

Would it be possible to build a single transistor Hartley oscillator by substituting a pancake (spiral) coil for each leg of the center-tapped...

Would it be possible to build a single transistor Hartley oscillator by substituting a pancake (spiral) coil for each leg of the center-tapped inductor, and then placing one coil flat on top of the other so the insulation between them takes the place of the cap? If the current in each coil is made to flow opposite to the other, could their proximity to each other also be used to vary th...

Shows how the power transformer is directly wired to two separate boards. Not sure how, or why, they'd want to do that. Shows the...

Shows how the power transformer is directly wired to two separate boards. Not sure how, or why, they'd want to do that. Shows the hole through which the transistor has to be soldered. Note the two resistors in plastic tubing that have one end so

I am looking for an inexpensive P-Channel enhancement node SOT-23 case MOSFET that will suit my design. See...

I am looking for an inexpensive P-Channel enhancement node SOT-23 case MOSFET that will suit my design. See http://siliconventures.net/images/P%20Channel%20MOSFET.PNG The M9 transistor will have a source voltage of between 18 and 28 volts maximum. Getting a MOSFET whose Source - Drain voltage (when off, in this case) is greater than 28 volts is no issue. I can easily get them for

Years ago on this group, someone worked this circuit out for me and I have finally built it. It has two problems. The input impedance is about...

Years ago on this group, someone worked this circuit out for me and I have finally built it. It has two problems. The input impedance is about 30kΩ not 500MΩ, and it rolls of way to early. I may have created the problems, I don't have the FET and transistor recommended, 2N4416 and MMBTH10. I used a BF256C and a MPSH10 through hole parts. Although I doubt that created the

Could some electronics guru here please clarify this ? The datasheet for the NPN BJT HFA3134(from Renessas Semi.) states: The HFA3134 and...

Could some electronics guru here please clarify this ? The datasheet for the NPN BJT HFA3134(from Renessas Semi.) states: The HFA3134 and HFA3135 are Ultra High Frequency Transistor pairs that are fabricated with Intersil Corporation’s complementary bipolar UHF-1X process. The NPN transistors exhibit an fT of 8.5GHz, while the PNP transistors have an fT of 7GHz. Both types e

Hi all I am playing around with a solar lamp, pretty simple like this https://www.pinterest.com/pin/540150549038731182/ However I do not...

Hi all I am playing around with a solar lamp, pretty simple like this https://www.pinterest.com/pin/540150549038731182/ However I do not (yet) have D2. D1 in my case is a Schottky 1N5818, and my battery 7.2V I am surprised how much reverse current I can get through the diode. Without the solar cell, it does not turn on. There is enough current through D1 to the transistor to turn the wh...

VDMOS nonlinear capacitance is modeled in terms of Vgd. Too bad a real MOSFET doesn't show a steplike change in Ciss as Vgd changes sign. ...

VDMOS nonlinear capacitance is modeled in terms of Vgd. Too bad a real MOSFET doesn't show a steplike change in Ciss as Vgd changes sign. (This is easily demonstrated with the gate charge test circuit, watching the waveform at low Vdd. The cutoff slope depends only on Vds, not Vgd.) So many decades of bullshit to sift through... Tim -- Seven Transistor Labs, LLC Electrical E...

I have a little transistor radio that was drawing excessive power from the battery. It was about 125mA at 6 volts which is 10 times too much. I...

I have a little transistor radio that was drawing excessive power from the battery. It was about 125mA at 6 volts which is 10 times too much. I found I could bend the circuit board to eliminate the problem. So, I studied the thing for an hour or so and found the problem had something to do with the audio output transformer. This radio uses an input and output transformer in a push pull a...

Hi I want to get a steady rising voltage, which is simple as constant current. Say, like a saw tooth but only first rising part and really...

Hi I want to get a steady rising voltage, which is simple as constant current. Say, like a saw tooth but only first rising part and really slow. (I do not want a timer, but a rising voltage) I was thinking of something like this using the Vbe of a transistor https://electronics.stackexchange.com/questions/53615/constant-current-source Also a similar thing can be done with an op-amp ht...

Hi So I wanted to check the VCE of a transistor in a small converter running at 100kHz, expected to see about 100mV above ground as...

Hi So I wanted to check the VCE of a transistor in a small converter running at 100kHz, expected to see about 100mV above ground as the saturation voltage of the NPN, increasing linearely since magnetising current increasing. I saw nothing like that, debugging and found the scope (Tek DPO5000) somehow saturates with high voltage inputs. The signal is a square wave of 100kHz, 25V peak to...

I'm designing a small simple circuit in which a MOSFET drives a low-power load. The very low frequency gate drive may, on rare occasions,...

I'm designing a small simple circuit in which a MOSFET drives a low-power load. The very low frequency gate drive may, on rare occasions, exceed the max Vgs rating of 12V by about 1V, possibly 2V. There are a number of ways to limit the gate voltage but I want to avoid them and keep the circuit as simple as possible, and it won't cause a disaster if the transistor fails. What do you thi...

The only problem that I may have created is the transistor, I used BC547B with HFE of 200 to 450 vs BC549C with HFE of 420 to 800. All I had...

The only problem that I may have created is the transistor, I used BC547B with HFE of 200 to 450 vs BC549C with HFE of 420 to 800. All I had in my junk box. I built a low noise amplifier, original design was for a 30v supply, I chose to correct the values for a 15V supply. Designer does have a 12v version, my values are close.  I did set an emitter resistor to have equal clipping....

Q. Relative power dissipation capability of TO-92 transistor packages (viz, Zetex E-line parts) vs. sot-23 packages. More on this in my...

Q. Relative power dissipation capability of TO-92 transistor packages (viz, Zetex E-line parts) vs. sot-23 packages. More on this in my next post, first some background. One of my design interests is high-frequency, high-voltage power amplifiers. For example, I'm doing a 45V, 5A peak, DC-10MHz amplifier. My design uses 20 TO-220F power transistors, mounted on a 200W fan-cool...

This is an about -30 dBu sine wave being amplified to about 0dBu by the triode section of a Sylvania 12EC8 triode/pentode "space charge" tube....

This is an about -30 dBu sine wave being amplified to about 0dBu by the triode section of a Sylvania 12EC8 triode/pentode "space charge" tube. The plate load is a single transistor gyrator/constant current source. Plate and heater currents are being supplied by a "China Special" boost converter module that's stepping up a 4 "C" cell battery pack. http://tinyurl.com/zeegduc Yick. Lots...

I'm making some replacement boards for a system I designed a while ago. 1980, actually. The power regulator board used a couple of LM376's,...

I'm making some replacement boards for a system I designed a while ago. 1980, actually. The power regulator board used a couple of LM376's, a nice little DIP8 voltage regulator that drives an off-board heatsunk PNP pass transistor. LM376 seems to be unavailable. But I can't find a substitute, namely a linear voltage regulator controller with foldback capability and external PNP pass tr...

Have a circuit that needs repair. Uses a TIP125 (NPN, Darlington) emitter tied to Vbb (~20VDC). Collector to load, then to ground. 1K resistor...

Have a circuit that needs repair. Uses a TIP125 (NPN, Darlington) emitter tied to Vbb (~20VDC). Collector to load, then to ground. 1K resistor (R1) pullup on Base to Vbb, and a second 1KR (R2) to the TTL controller. Problem is of course, that R2 puts the ~20VDC to the TTL output gate on a 74LS138. Trying to solve this without a driver transistor. The circuit is for a 1ms ~20V strob...