Harvard H407 bleep?

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The Collector
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Re: Harvard H407 bleep?

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Put in an extra red one so that the meter glows red on TX like a Mustang ;)

I was always into messing with new colours, different knobs and LED's etc. (apart from in the signal meter) from about the age of 17 or 18.

Sometimes my mad ideas worked, other times they just looked mad!
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Re: Harvard H407 bleep?

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Black Spirit wrote: 24 May 2019, 21:41 The green Leds in the Icom ICB1050 are common cathode while the Harvard homebase are common anode, The common anode will work but you will need to reverse the polarity to the display and all the diodes [Channel 9 etc]
Just in case - and for future reference - the other displays I was looking at at the time were green ones out of the Mustang 3000 and the Harvard 402MPA. Are they the right polarity does anyone know as they both use the Amstrad board I believe?
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163TM847
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Re: Harvard H407 bleep?

Post by 163TM847 »

The green ones from a Mustang 3000 will go straight into an Amstrad/Harvard homebase, I think i have one green block from a Mustang here
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Re: Harvard H407 bleep?

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Thanks for the info Nick. That's something for Rich to have a think about then if it's just a case of swapping the display block itself.

Now...how easy would it be to fit an Amstrad's complete LED signal display board into Rich's Harvard homebase? Get that jigsaw out Rich...
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Re: Harvard H407 bleep?

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I got my Dremel and latex gloves ready :D
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163TM847
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Re: Harvard H407 bleep?

Post by 163TM847 »

Too add a LED meter is easy enough, A TL508 will do the job.

I have a fully working [But scruffy] harvard homebase with original mic here for £15 if anyone is interested, Its the one with silver edges and speaker grill.
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Re: Harvard H407 bleep?

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An earlier 404 model I believe. Sounds a bargain for someone to have a play with.
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