Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

Questions tagged [power-supply]

Questions regarding devices for supplying power to electronics.

32 questions
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What sources of power are useful in emergency situations?

Situations that call for emergency operating usually have some hams working in field conditions. Relying on the mains grid could be problematic. A lead-acid battery would probably be heavy to lug around should the operator need to relocate in a…
VU2NHW
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Practical differences between switching and linear power supplies?

Power supplies for ham radio equipment (and other equipment of course) seem to come in two flavours: switching and linear. The switching gear tends to be cheaper and smaller as well as more efficient. My understanding is that switching supplies…
Jim MacKenzie VE5EV
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Powering transceiver and SWR/power meter from same supply?

I'm mostly sure this will be ok, but I'd like to confirm. I have a switching power supply (can't remember the model right now, but it's for ham use, 13.8V/30A) and I'd like to power both the FT-857D as well as the power/SWR meter from it. Is there…
Rimio
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How can I sound-proof my generator?

Looking for advice to semi-soundproof my extremely noisy gas generator, which kept everybody edgy on Field Day. It's a real powerhouse, but the cost of that power is my hearing. I'm looking to buy or homebrew something lightweight that I can use to…
Noji
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2 answers

Stacked shell inductor — what's its function/use?

I have a device of copper and iron (about 8 kg) which looks like two shell inductors joined so that there is some coupling but high leakage. The windings seem to be identical. Each is a single continuous winding with 4 intermediate taps. I did not…
Merlin3189
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4 answers

Are there any cons of running shack on battery?

I'm building a low-power shack to operate on non-licensed bands (UHF PMR 0.5W + HF CB 4W). I don't have any "RF-grade" sources of 12(-ish) volts and don't want to buy a specialised power unit. I'm thinking of running the whole setup from a 12V…
Alexander
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5
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Using an SDR on a Laptop with Noisy Power Supply

I'm going to start this off by saying I'm very new to this and I don't really know a lot so any detailed information would be much appreciated. I have just started using an SDR (a cheap RTL model) with my MacBook Pro laptop. The laptop itself is a…
TitanShadow
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3 answers

Power connector for a HPA

I've got two Kuhne's HPAs rated at 12V, 10Amps. The HPAs have power connectors circled in blue. Is there a specific jumper with a compatible head that I could plug directly into this connector? I'm trying to avoid soldering if possible.
Moses Browne Mwakyanjala
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Calculation of transceiver current draw

My radio manual says its current draw is 22A. But in my naivety I would have calculated as follows: If the radio 'put out' 100W and I have a 13.8V supply then (using the formula power = VxI) 100W/13.8V = 7.2A. So, it looks that I'm way out…
KHWP
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Is using a generic DC 3V adapter dangerous to a radio?

I have the mini Eton radio and it has a DC 3V port but I haven't been able to find the official plug. Is using a generic one safe? How do i know if I found the correct AC adapter? It goes through 2 AAA's in two days! So I definitely want an…
verve
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Does using a computer SMPS to supply a transceiver bleed hum into the signal?

A dedicated/custom power-supply for an HF rig may, on occasion, be unavailable. The internet lists any number of articles on the subject of modifying a computer…
VU2NHW
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How to figure out my car battery's capacity?

I was participating in an emergency radio training and I was asked how long I could operate. I'm using an old car battery, which was sometimes not capable of starting the car in winter, which is why I have it. It has a nominal capacity of 45Ah. Is…
Thomas DK3TU
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power supply / LiFePo4 battery backup compatibility

I want to create a battery backup for my radios. Initially I'm thinking of using an Epic PWRgate and a LiFePo4 battery, so the battery is charged by the same power supply that's running the radios. The LiFePo4 batteries require a charge voltage of…
Brad Mace
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Ham Variable Lab Power Supply

I'm looking into purchasing a mobile radio (TYT TH-9800) for my Jeep Wrangler. I am hoping to be able to use it in my apartment as well. Since I'm going to need a power supply for this, I think it would be great to pick one up that can double as a…
mosfet386
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Does the varactor bias supply have to be independent of Vcc?

A quick follow-up to How can I tell the frequency without an oscilloscope, or frequency counter? My supply is a transformer plucked from a dead power adapter rated for 1.5A. This is rectified cap-filtered, then Vo manipulated through an LM317 with…
VU2NHW
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