A few days ago genebren asked about experiences with the SAG-55 Hot Air Gun. It's quite new and looked pretty good on paper although no E14 members admitted to owning one. I've had an Atten ST862D hot air gun on my wish list f...
I spotted 2 Hewlett Packard 3784A Digital Transmission Analyzers on Ebay recently. I thought they might be interesting for the boxes but when I looked more closely I realised that they were a bit more interesting because they should be able to talk t...
I got quite lucky (I think) at an auction a couple of weeks ago and got a lot of three Neutrik RT1-M digital audio test boxes for £99 (including commission and VAT).
It's quite an old design with a slightly quirky instruction set, but very ...
I started this project a while ago (September 2024) but just picked it up again. To get the best out of this blog you will need to download the combined User and Service Manual for the HP59313A, which you can find at: https://www.keysight.com/u...
This blog is about my test rig for measuring DC-Dc converter efficiency in the range Vin/Vout 2-50V and Iin/Iout 1-10A. It can also be used to measure the power consumption of DC systems in same range.
The test rig ready to run (power supply and devi...
Recently I blogged about a mains powered isolated dual low noise power supply I had built.
scottiebabe suggested that for some purposes it would be easier and cheaper to use a USB isolator.
These can be bought quite cheaply from Amazon and very...
Introduction
I’m working on test rig for accurately measuring the efficiency of DC-DC regulators or converters. It uses 2 precision current shunts to measure the input and output current. These need very low noise pre-amplifiers which must each...
The first part of this project kicked off with a blog “First Design with KiCad (8.0)” about 4 weeks ago. The idea was to build a replacement for obsolete TO3 can linear voltage regulators using the Linear Technologies (now owned by Analog...
I’ve been using the same PCB design software for over 20 years (Easy PC) and it’s served me well during that time. It’s had an update pretty much every year and it can still load files from 20 years ago. It hardly ever crashes and I...
I recently bought this instrument on Ebay - it's quite an old design and if you fancy one the 3325B might be a better bet since it has a much more modern processor and a few extra functions (but will cost more).
It was first released in 1979, at ...
A while ago (October) I ordered a coil winding machine from Alliexpress.
It took a while to turn up (6 weeks or so) but it was free shipping.
Several vendors sell the same machine with slightly different labelling and features. The prices vary ...
In a recent thread ggabe mentioned using the AD8367 as a true RMS detector.
I'd never encountered this chip before and was interested in what it could do. The official eval board from AD costs about £110 which is a little steep for a ...
In a recent thread Shabaz was wondering how easy it might be to make a wideband true RMS detector using a surface mount thermistor and resistor.
This is a first very crude and simple experiment to find out.
I soldered tiny bare wires to a 10K 0...
After seeing it recommended by /members/shabaz I bought myself some Polydoh. It's a low melting point plastic supplied as little spheres. You put it in hot water and it goes clear and moldable. I've used it to make quick covers for pin headers....
In the last blog about this board, I talked a little about the PSRAM chips. This blog is about getting them working and some digression into memory controllers in general.
I have two AP Memory APS6404 chips on the board and directly attached to the F...
In the first blog of this series there is a schematic which shows the two AP Memory APS6404L Pseudo SRAMs connected to the FPGA.
These can be clocked at a maximum rate of 130MHz, but there are some issues in going that fast – firstly the maximu...
Having built the boards, I was determined to get one running before Christmas.
It went quite well.
The first tiny snag, that wasted a little time, was wondering why the 3.3V regulator (LM1117) was only outputting 3.0V. It turned out that with no load...
The boards came from PCBCART this week. They often send a couple more than ordered but this time got carried away and sent 20 although I only ordered (and paid for) 10. It's one of the reasons that I like them. Most PCB places make extra boards t...
The Efinix FPGA board has a connector for an SPI interface OLED display driven by the GD32103 processor.
I’ve made some little experimental display controller boards which use this processor and can run the same code as the FPGA board processor...
Die hard E14 blog readers will be familiar with my blowing the trumpet for low cost simple FPGA development work and I’m at it again.
I’ve just done some work for a client where they really wanted to use the Intel(Altera) Max 10 and...
Recently /members/andrewj posted about some issues with heatsinks. It so happened that he was thinking of using heatsinks similar to one I'd already chosen for a resistor based adjustable load.
I'd run into some issues using active loads with...
A low-cost VI PlotterI’m currently working on a project that uses custom made LEDs emitting at an unusual wavelength. One of the most important characteristics is the current against voltage curve. This is hard to measure because the chip is tiny and...
This blog is about implementing an 8 bit CRC on an STM32G071xx micro. Several other ST micros have the same CRC hardware system so it will apply directly to them. There is also some discussion of CRC in general. Pretty much all this stuff is on the w...
I did a preliminary blog about this on May24th and promised more when I got the boards. It's a bit of a mixed story some good news, and some less good. I'm posting the LTSpice model and the schematic again , to avoid endless cross referr...
