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News, Updates and Other Minutiae

September 2023 Long time between drinks, but not much happening on the tech front at the moment. Added another couple of rants to the rant page.

January 2023 Updated the AD9833 VFO code to use a 12F1840.

December 2022 Added rant about todays useless (internet) search engines.

November 2022 NEW Project An AD9833 Based Simple VFO. FT101ZD VFO project updated.

October 2022 A replacement internal DDS VFO for FT101Z/ZD rigs. Because the worlds postage system has gone totally bonkers and it is not possible to send a small pcb anywhere except at extreme cost, I am slowly making available the option to purchase pcb's from Pcbway. First up is the Simple DDS VFO 2017 project pcb. Others will be added over time. Noise Canceller kits available again- see Noise Canceller page.

Privacy Policy uploaded. GPDR and all that stuff In accordance with various bits of legislation around the world, either currently in force, about to come into force or proposed, you will now find that annoying "We use cookies" notice at the top of this website. The full Privacy Policy is available at the Privacy Policy link in the footer at the bottom of the page. (If you don't know what GPDR is, Google it. Real scary shit for ANYBODY with a web presence.)

The Gear in the Shack

Some photo's of the equipment in the shack. First up, an FT7. Considered to be a fine rig in it's time when it came out in the late 1970's. I haven't fired this one up yet, so I have no idea what condition it is in operationally. Cosmetically, it's not too bad, but then nobody can see it over radio, can they.

picture of ft7

Next up is an FT757GX. From it's serial number, it is one of the very first one's from circa 1983. I bought this one cheap with a receive problem according to the previous owner. Why did I buy it with a fault? Well, one of my activities is PIC programming, so I want to look into doing a replacement cpu for this rig at some stage.

picture of ft757

The fault is supposed to be that it drops out on receive occasionally but tx is fine. Most likely causes of this (in no particular order), faulty/aging xtals, faulty trim-caps in the oscillators and a very common one, faulty diodes (this model uses diode switching instead of relays for much of it's rf switching). There are relays used for power switching and it's possible one of these is faulty. On the test equipment side of things, I have a Marconi TF2015 signal generator, a CTE 1gHz spectrum analyser, UNI-T 100MHz digital storage scope and various multimeters on the commercial side. Amongst the homebrew test equipment, there is an LC meter built from information on the net, an RF Powermeter designed by OZ2PU and published in Elektor magazine, various frequency counters and a valve/tube GDO.

picture of tf2015 signal generator

Marconi TF2015 signal generator. 10MHz - 500MHz range.

picture of cte spectrum analyser

CTE spectrum analyser. This unit has internal batteries so that it can be used in the field. All I can say is, you need muscles upon muscles to cart this any significant distance. It is a really heavy brute with batteries in.

homebrew lc meter

The LC meter built from information on the 'net. 16F628 PIC based.

homebrew rf powermeter

OZ2PU RF Powermeter. Contains an AD8307 and 16F876 and good to approx 500MHz.

valve gdo

As you can see, the GDO is complete but in pretty rough condition. I'm still debating whether to power it up or not (after doing the necessary safety checks, of course).

Tech gdo1Tech gdo2
Tech gdo3Tech gdo4

Tech TE-15 GDO - bought recently (Jan 2024), from the original owner, who bought it in the 1970's - it is in immaculate condition, looks like it has never been used.

FT7 manual FT7 high resolution schematic

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