Quote:
Originally Posted by Ian - G4JQT
Did I include details in the article for anyone who wanted to wind their own?
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Yes, Ian, you did, although a fixed-value home-wound coil would have needed a variable trimmer to give some frequency adjustment capability. The specified coils are ideal and very cheap.
Quote:
Originally Posted by Ian - G4JQT
I didn't include an 'ON' LED in the design as it would nearly double the current consumption...
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Indeed it does, but mine draws 15mA and an alkaline PP3 should last around 40 hours, which is more than adequate for the occasional use this device is likely to receive at G4SPZ.
Quote:
Originally Posted by Ian - G4JQT
I really like the label you put on yours. Very professional! White-on-black and printed on what?
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Nothing more than Microsoft Word, using white text with dark grey "Shading", and this function is available under "Paragraph". It's actually a very dark grey background, which looks less stark than black. I printed it on ordinary 80gsm paper, cut it out and stuck it to the case with Pritt Stick! No doubt a matt photo paper would be more durable, but if it ever gets tatty I can always print a replacement. The label also hides the slightly oval hole for the on-off switch, which I managed to drill slightly out of place...
Quote:
Originally Posted by Ian - G4JQT
The wiring error... yours or a misprint in my article?
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My error entirely, Ian. In planning the layout of the circuit on matrix board, and trying to minimise the space required, I inadvertently put the oscillator coil the wrong way up so the tapping was nearest the top, not the earthy end. This led to the FET being turned hard on with no oscillation. I swapped over the connections to the coil and away it went!
Thanks again for a really good design. It compares very favourably with a professionally manufactured AM-03 which I bought some years ago. The Mini-Mod has half the component count of the AM-03 but produces just as good quality and amount of output.
Kind regards,
Phil