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Couldn't resist ordering one of these [Teensy 4.0] today.


Active Member
I don't know what I will do with this it but it does appear that I will be doing it faster than I would without it [Is that a reason? Yes, I think so]. I don't care, toys are fun.

It does look impressive.

Nigel Goodwin

Super Moderator
Most Helpful Member
Well I couldn't resist these, so I ordered 3 :D arrived today - but they use USB-C :banghead:
I don't have a USB-C lead :arghh: - so 've ordered one of those, from RS Components, so it'll arrive Monday. However, I've fitted a SIM card, soldered a couple of 18650's to the end of the battery lead - and admired it a bit :D


mvs sarma

Well-Known Member
Good morning Nigel after a 3 year GAP, I am back here. ,
i too had bought one in order to make one SWR and Power meter, designed by Johan the details are at Groups.io under RADIOSTUFF.




Active Member
Came pretty quickly...I am tempted to play around with it this weekend. Also, there is an interesting thread at eevblog about it and their model and so on...new shiny penny d'jour or $20 monster? Don't know...don't even know what I will do with it, maybe a direction of arrival machine - been wanting to try that.



Active Member
Today, I decided to check out the Teensy 4.0 and I had something particular in mind.


Intermittently, I have been exploring the PIC32. In particular the MX270F256B. It is available in a through hole DIP in both 40MHz and 50MHz maximum clock speeds. I was exploring using the internal RC oscillator rather than an external crystal. You have to set up some multipliers and dividers to get the speeds. Specifically, I was testing using both 40MHz and 48MHz clocks (there is no way to get 50MHz using the RC as far as I can see).

I wanted to see if I was setting the oscillators correctly for 40MHz and 48MHz.. Not the absolute accuracy but was I doing what I thought I was doing with the oscillator set up. I should mention that I don't have a real frequency counter.

I used a simple program that toggles an IO bit on the PIC. Then I used the Teensy 4 to measure the frequency (there are actually a few example programs for frequency measurement).

So: 40/48=0.833. At 40MHz, I read toggle frequencies of 3337142 and at 48MHz, I read 4002718 (the last 3 digits will vary but those are typical values that I saw.


Edit: typos
Last edited:


Well-Known Member
Phew, even atmega328 is more than enough for most of my stuff!

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