Harvard H407 bleep?

A forum for the discussion of matters of a technical nature. All such activities are undertaken at the readers discretion and own risk. If you don't know what you are doing, don't blame us if it all goes wrong!
User avatar
The Collector
Legend
Legend
Posts: 5930
Joined: 23 Jan 2010, 19:26
Location: Bristol-ish

Re: Harvard H407 bleep?

Post by The Collector » 25 May 2019, 14:24

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!

User avatar
The Collector
Legend
Legend
Posts: 5930
Joined: 23 Jan 2010, 19:26
Location: Bristol-ish

Re: Harvard H407 bleep?

Post by The Collector » 26 May 2019, 19:00

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?

User avatar
Black Spirit
Veteran
Veteran
Posts: 4064
Joined: 16 Mar 2009, 19:30
Location: S.Wales

Re: Harvard H407 bleep?

Post by Black Spirit » 26 May 2019, 21:19

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

User avatar
The Collector
Legend
Legend
Posts: 5930
Joined: 23 Jan 2010, 19:26
Location: Bristol-ish

Re: Harvard H407 bleep?

Post by The Collector » 27 May 2019, 07:54

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...

User avatar
NightProwler
Veteran
Veteran
Posts: 2767
Joined: 08 Feb 2012, 22:31
Call Sign: 163TM186
Location: South Wales

Re: Harvard H407 bleep?

Post by NightProwler » 28 May 2019, 15:32

I got my Dremel and latex gloves ready :D
Shorter of breath and one day closer to death

User avatar
Black Spirit
Veteran
Veteran
Posts: 4064
Joined: 16 Mar 2009, 19:30
Location: S.Wales

Re: Harvard H407 bleep?

Post by Black Spirit » 30 May 2019, 10:50

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.

User avatar
The Collector
Legend
Legend
Posts: 5930
Joined: 23 Jan 2010, 19:26
Location: Bristol-ish

Re: Harvard H407 bleep?

Post by The Collector » 30 May 2019, 21:43

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

Post Reply