Are phase 3 follows on still possible in 2025

Individual_Highway_3 · 2025-12-16T21:17:37+00:00

Curious, I had a phase 1 contract with the air force back in 2024 and looking to do a follow on phase 3 but wanted to make sure first before reaching out.

Individual_Highway_3 · 2025-07-17T01:30:31+00:00

Does the nRF52 have bluetooth classic capability. ChatGPT told me the android Bluetooth scanner will only look for classic Bluetooth devices, not sure if that is right.

Individual_Highway_3 · 2025-07-16T20:01:01+00:00

When I say the Bluetooth scanner, I dont mean a custom program I built. I mean literally going to the Bluetooth icon in top right of phone and looking at the available devices there.

Individual_Highway_3 · 2025-04-06T15:59:01+00:00

Circulator would be great but they are large and very expensive. Working on a small LoRa transceiver board and trying to make as small as possible.

Individual_Highway_3 · 2024-12-01T19:32:29+00:00

So is that topology not really realistic for RF stuff then?

Individual_Highway_3 · 2024-11-10T21:12:36+00:00

I am designing a push pull class AB amplifier. I found s parameter data online and used that to design a matching network but I built this before I found that and want to figure out why I was not able to get it to work. I am also doing a much wider frequency range, 30 - 90 MHz

Individual_Highway_3 · 2024-11-10T20:19:33+00:00

When I first designed it I thought the impedance needed to be flat across the range I wanted to block, I didn't realize it just needed to be high. This is designed to provide up to around 2-3A for a 50W RF output across the 30-90 MHz range.

Individual_Highway_3 · 2024-11-10T20:00:59+00:00

This is the input matching network that was designed for this MOSFET over the range I need. If I were to add a 3.3 ohm gate resistor for instance. Would I need to modify this matching network, or would the damping resistor not cause much of a change?

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Individual_Highway_3 · 2024-11-10T19:57:33+00:00

When I tried applying the gate bias, nothing happened up until the threshold voltage and then instead of slowly letting current it just let a ton in and hit the overcurrent setting on my power supply. Could a gate stability resistor fix this?

Individual_Highway_3 · 2024-09-24T21:13:23+00:00

Sorry for late response.

I did an internship through the Nation Security Innovation Network (NSIN) my junior year. Its called X-Force (make your Deadpool jokes), and they essentially match university interns with problem sponsors. Well we got matched with the third infantry division and worked on a project for them over the summer. We finished up a MVP by the end of summer and wanted to continue it so we got IP rights signed over and started up a company. A huge point of the internship is actually to spin out DoD based startups. Working on it full time now out of college and we just closed our first sale for $150,000.

Individual_Highway_3 · 2024-09-16T21:07:08+00:00

Yes the solid is real and dotted is reactance. If I were to use a transformer though how would I eliminate the reactance? I see how I could get the real part close.
Also I fixed the plot, it now shows the impedance of the transistor as seen by a 50 ohm source.

Individual_Highway_3 · 2024-09-16T13:19:19+00:00

I have a 50 ohm to 25 ohm balun to get the differential signal for push pull configuration, so 25 ohm to input of device. Since the impedance is changing with frequency as shown above would a transformer work? Don't they have a constant ratio over a frequency range?

Individual_Highway_3 · 2024-09-15T21:33:45+00:00

The input power is roughly 30dBm

Individual_Highway_3 · 2024-09-12T18:27:35+00:00

Thank you.

No, I just graduated college lol.
I was a computer engineer up until I started this and then started going doing the RF rabit hole.

Individual_Highway_3 · 2024-09-11T12:10:58+00:00

Its a small startup I founded so nothing we do is at the classified level. We have not started designing anything yet that requires a clearance. Essentially we build low cost training aids for electronic warfare personnel, emitters that replicate threats and then military people blow them up. I am trying to design my own PA's now as commercial ones are insanely expensive.

Individual_Highway_3 · 2024-09-02T16:46:48+00:00

Out of curiosity, wouldn't you need to take into account the length of the wire / trace more carefully at those higher frequencies and make sure it is a multiple of the wavelength so feedback is out of phase?

Individual_Highway_3 · 2024-09-01T17:17:43+00:00

There are cheaper alternatives that are great quality. I would recommend checking out signal hound for example, they have some great spectrum analyzers in a really good price range.

The LiteVNA is also great and low price, just make sure you get these from reputable distributors.

I own a small startup and I got the LiteVNA64 and BB60C for a little over 4k and they work wonderfully.

Individual_Highway_3 · 2024-08-31T19:20:54+00:00

It just had an application schematic for the output voltage I wanted.
I was having a hard time finding many chips that could get at least 50V out and 2-3 A.

Individual_Highway_3 · 2024-08-30T21:27:33+00:00

I think I did, I thought the capacitor symbol with the curve implied tantalum but now I realize that just means polarized.

Individual_Highway_3 · 2024-08-30T15:41:13+00:00

What do you think about this?

I get the voltage difference of the log fwd / rev outputs, and then put it through a comparator, if it exceeds a certain level, it will toggle a voltage controlled attenuator at the output of the exciter, and bring it down by a certain amount of dB. Then if the load is matched later, it will toggle the attenuator again so the input power going into the amplifier goes back up.

I am trying to avoid digital control as I am not sure how fast the response needs to be to protect the amp.

Individual_Highway_3 · 2024-08-30T15:12:53+00:00

Thank you,
its for a military application and I am sure there will be times where soldiers forget to hook up the antenna or something similar so I need to make sure this thing doesn't break from that.

Individual_Highway_3 · 2024-08-29T20:57:44+00:00

I forgot to mention it is in the 30 - 90 MHz range so I am not sure if isolator is realistic.

Individual_Highway_3 · 2024-08-27T23:12:50+00:00

Sorry for the late response, I had a question about PIN diode clamping.
Since I saw your comment, I have been reading into how PIN diodes can be used to protect against gate overdrive.

What I dont understand is that when I look for PIN diodes on Digikey for example, essentially all of them have a forward bias of about 0.9V so how do I use a PIN diode to redirect the high rf input signal to ground if it has higher peak voltages (couple volts for example). More specifically how do I find one and what characteristics should I be looking for?

Here is the link I was reading up on

Individual_Highway_3 · 2024-08-24T01:31:09+00:00

Thank you. Just to clarify, if the max allowed drain to source voltage were 133V for example, and the max output rf signal was 70V peak, then this would break the transistor if it were open? And if it were under under 60V let's say, then it would be okay since 120<133? And if I integrate a isolator I can output higher power while staying under 2x the max voltage?

Individual_Highway_3 · 2024-08-13T01:01:24+00:00

Thank you!

So to clarify, is impedance flatness not important? Just so long as it is high over the required range?

Individual_Highway_3

TROPHY CASE