Questions tagged [substitution]
Involving or pertaining to electronic component or circuit substitution.
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Replacing clock crystal with signal generator [closed]
I have this blob chip module that I'm reverse-engineering, that ran off a 12 MHz crystal. In getting the module out I broke the crystal.
It was a two pin through hole component. Big orange blob marked ...
2
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Info/substitution for National Semi's obsolete S-1122 transistor?
I am debugging a mid-1970s piece of printer equipment and have traced a failure to what looks like a bad transistor. But I can't find a data sheet for it (or a useful substitution). It's a metal can ...
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Substitute 2N3055 with 2SC5200 in the John Linsley Hood 1969 amplifier circuit
Can I substitute a 2SC5200 for the 2N3055, without any other modifications to the following amplifier circuit? Input voltage is 24 V and biased to run at 1.2 A.
schematic source : https://sound-au....
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Li-po battery: determining compatibility for replacement battery and charger
I want to find substitute batteries for a pair of heated boots (heating element in the boot sole) with larger battery capacity for longer operating time. The boots came with two 8 V, 2600 mAh ...
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When is it appropriate to mix 74LSxx components with original TTL 74xx?
I spend almost all my tinkering time with 1970s era logic circuits, which use almost all original 7400-series TTL. I do a fair bit of repair and am now starting to design additional logic to work with ...
2
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Substituting an outdated FPGA with another one from the same family
I have a board with an Altera EPF10K30RC240-4N. It has an EPC1 next to it, which I found is the "Configuration EPROM". I assume this stores the "program"?
The FPGA is not ...
0
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Substitute for MAX865EUA-T [closed]
It's been few weeks I'm searching for a substitute for my MAX865EUA-T (datasheet). I need a component able to do a +10V/-10V output with a +5V input, this component was perfect for me since it's ...
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Need help identifying resistors to use as a substitute for my OTG cord project
I'm trying to put together an OTG type C to USB cord and I don't have the required 5.1 kilo-ohm; resistor but I have these. Can I use one or a combination of 2 or 3 to accomplish my goal?
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6 A, 30 VDC relay as substitute for a 5 A, 30 VDC relay
May I confirm on this forum if a 6 A, 30 VDC relay can be used as a substitute for a 5 A, 30 VDC relay? They have the same number of pins as well as holding coils orientation.
I purchased a relay as a ...
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Getting a small AC "reference" from a DC power supply?
I have a 1970s-vintage video generating board that I'd like to do some work with. I do not have the PSU that it was meant to be connected to. The board wants +/-5V, -12V DC, plus a small 6V AC "...
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Need advice in repairing my obsolete 44-year-old OEM Ovation acoustic guitar preamp
Preamp (9VDC): 6 capacitors (4 MMKO box film caps and 2 CAPAR axial 4.7uF 50v electrolytic caps), 1 3-pin junction transistor (M2N5458), 2 unknown transformers, 5 resistors. See attached image.
...
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Substituting components (schotky diode, MOSFET) in my circuit
I have the following battery protection circuit (mostly it's just a copy of MAX17320 reference design provided by Maxim). It's meant for a 2 cell li-ion battery pack designed to power a small robot. ...
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Operate servo based on AC voltage: solenoid replacement
In short, I’m trying to find a substitute for a solenoid in a system that was operating based on 120V. The servo needs to rotate a little shaft about 45 degrees when the voltage comes on, and then ...
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Can I substitute SN74LVC1G04 (single inverter) for SN74LS00 (quad inverter)? (re: simple GAMEPORT to MIDI cable?)
I'm trying to design a simple GAMEPORT to MIDI adapter/cable. However, the original design specifies the 74LS00 which I think is used as a buffer:
http://midi.teragonaudio.com/hardware/pc_intfc.htm
I'...
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Substitution for an unavailable flash memory chip? [closed]
I need to find a replacement for a particular flash chip that is currently in a device.
The chip in question is the KH25V16066
https://www.macronix.com.hk/Lists/Datasheet/Attachments/272/...
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Do circuit reclosers of substations respond to any fault on the low voltage side of distribution transformer?
As I don't have any practical experience in power distribution networks, I'm pretty confused about a few things.
Typically a lot of transformers are connected to an 11KV distribution line ( 11KV ...
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KA336 replacement parts
Can you replace a KA336 with a TL431 directly?
I have a circuit board with a broken KA336 and I can't find it here in my country, not even the LM336. It is a 2.5V shunt regulator.
The adjust pin on ...
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MOSFETs not activating - is this transistor the problem and can it be subbed?
I'm trying to repair a DC motor controller that moves a caravan. The positive side is relay switched, and it turned out that the negative side of the motor supply was switched by a pair of IRF3205 ...
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Transistor substitution guidelines? (and the BC147A)
I'm in the US and fixing a vintage German integrated amp which has a crackle static issue I've isolated to a transistor in the preamp section. The transistor is specified in the schematic (below) as a ...
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Substituting an inductor - cannot find any pieces containing inductance needed
I am a beginner electronics hobbyist trying to follow an old schematic / instructions to build a theremin.
I have all of the pieces except one. This piece (Toko 154ANS-T1019Z) calls for a "68 µH, hi-...
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Diode substitution for FMXG26S
I been hunting for an equivalent for a Diode in TV Power Supply - its a FMXG26S. Does anyone have any idea of an equivalent? Or where I can look one up? The datasheet advises the following for the ...
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Passive Component ratings displayed on schematic - Use actual value or design requirement value?
When placing a passive component such as a cap or resistor on schematic, most people usually place the relevant rating (usually power for resistors, voltage for caps, and current for inductors) next ...
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Substituting solid wires for stranded
I have 100' of 2x7 (14) individually insulated 18 ga. solid conductors( I think it is communication cable) I would like to use in lieu of 16 ga. stranded wire for a gate opener. Is it doable?
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Wondering if I can change a cap value in a design
I am assembling a circuit from the ESP32 reference design.
Looking at value C1 page 18 https://www.espressif.com/sites/default/files/documentation/esp-wroom-32_datasheet_en.pdf (10uF) but I don't have ...
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Meter fuse availability/substitution conundrum
I own a Brymen BM235 multimeter, among other test instruments. While it's a nice multimeter, I have one problem with it: the fuse for the mA jack is a Siba 7017240.0,4, and nobody even bothers with ...
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Can a thyristor be built from two transistors?
Supposedly, an SCR/thyristor is just a simple, four layer PNPN semiconductor.
If that's the case..
When a circuit calls for a SCR/thyristor, and there isn't one available, can it be substituted by (...
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Can I replace a NUP2105L voltage suppressor with a NUP3105L?
Someone gifted me a device to read electronic control units from cars and trucks. They gave it to me because they don't use it and they have also removed some components from it to fix another device.
...
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How would a transistor's hFE affect a phase shift oscillator?
I have a phase shift oscillator circuit from a drum machine that I would like to reproduce as faithfully to the original as possible. My problem is that the 40 year old design uses a transistor (...
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substituting transistors and diodes [closed]
I'm a new hobbyist, I need a tip 121 transistor and a 2N4148 diode. I'm using the site taydaelectronics.com. This site doesn't have these items. A friend tells me that there parts can probably be ...
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Can an X-class safety capacitor be used in series with a load (i.e. where steady current flows through it)?
Many applications that need a low voltage supply that is not isolated from the mains use a capacitive dropper circuit to get it -- an example is shown in the schematic below.
simulate this circuit &...
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Slipping in an external adapter [duplicate]
I have an Atari 1040ST with a half-bad power supply - Along with two 5v Red wires that Are good, there is a Blue wire that requires 12v .9A (aka 9mA??) - With A/c on, it's measuring at 10.73v (on the ...
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Which MOSFETs can I use to replace these faulty obsolete ones?
I've had some transistors fail on a PCB, but I can no longer source them as they have long reached EOL and are now obsolete.
The part numbers are as follows (linked to the original data sheets):
...
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SRU-12VDC-SD-C vs SRD-12VDC-SL-C
I'm following this guide [1] to made a Z-Wave compatible doorbell and it requires a SRU-12VDC-SD-C relay. I know nothing really of electronics and have found a SRD-12VDC-SL-C relay on Amazon [2] ...
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what is the use of ultrafast diodes in wireless battery charger ckt
Instructable
I am working on a wireless charger that uses a ZVS Driver circuit for the transmitting end. This is its circuit diagram:
I have attached the instructable where this came from. Wireless ...
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Replacing a 8 ohm Speaker with a Piezo. Will it work?
Like Replacing a piezoelectric speaker with an electromagnetic one, but the other way round.
simulate this circuit – Schematic created using CircuitLab
A DC squarewave will turn on and off ASW ...
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Identify/substitute an SMD MOSFET labeled "540N 88KFG" for LCD monitor repair
I'm trying to repair the logic board of an LCD monitor that died while giving off a burned smell.
It seems that an LCD driver chip and a MOSFET (I think) burned out. The chip was easy to identify (...
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MCP602 alternative?
What can I substitute in place of the MCP602 in the following circuit? It is a pulse rate detector.MCP601/2/3/4 are not available where I live. I have attached the relevant instructable and the MCP602 ...
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What is the difference between the substitution principle and Thevenin theorem?
The substitution principle (as seen in this book; in italian, sorry)
Let A and B be any two part of an electrical network with voltage and current sources and only resistances, connected by
...
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unusual transistor markings "C8550"
I am repairing a "wall-wart" charger for a Black and Decker battery powered edger which uses a 12 volt/7 amp hour battery. It has ceased to deliver charge current to the battery but the half wave ...
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How to choose an alternative for a specific BJT transistor?
I'm trying to reproduce some circuits with electronic pieces that I've at home. Unfortunately I miss some recommended transistors so I'm trying to understand how to replace them with an alternative ...
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Substituting capacitors
I have a nicely-spec'd wireless router that doesn't work any more. (Sorry, I don't have a schematic, but it's an Asus RT-N16.) I popped it open and found that it has one capacitor with a bulging top....
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No germanium diode available for small crystal radio -- can active components handle the task?
I know that germanium diodes are trivial to find online, but as this is for a demonstration I'd rather not spend $6-7+ on shipping for a single 5 cent part for a project that's academic in exercise ...
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Is there a relevant difference between these capacitors?
I am planning to try designing a board that incorporates a switch-mode DC-DC converter, using this Texas Instruments reference design for their TPS54386PWPR ...
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Can I safely substitute a 4.7uF cap for a 5uF cap?
I'm working on a circuit that calls for a couple 5uF caps. I have 50v and 25v 4.7uF at my workbench. No cap voltage is specified in a schematic or parts list. The circuit has 12VDC coming in, one ...
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What is a secondary transformer?
On a number of projects I'm building, there's a transformer between wall power and device power. In the parts lists, the transformers are usually designated by "12v secondary transformer" or "18v 4a ...
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Can I substitute a mono potentiometer for a stereo one?
I have a PCB for a headphone amp that has a 6-hole pad for a single potentiometer. I've only got 3-pin ones in my box o' parts. Can I substitute the mono pot for the stereo pot, tie the sets of pads ...
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Question about long-term support for legacy board designs
This question is summarized from a discussion on the Electrical Engineering StackExchange chat.
It is reproduced here in hopes to generate a discussion with long-term value
Question for anyone with ...
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How do I determine if I can safely substitute potentiometers?
I've got a number of audio projects on the workbench, and of course, each of them requires different potentiometers. Instead of waiting for another box o' parts to arrive, can I substitute? What are ...