Motorola MHW2723

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G4EWJ
Posts: 711
Joined: Wed Feb 17, 2010 10:11 am

Re: Motorola MHW2723

Post by G4EWJ » Thu Feb 28, 2013 4:58 pm

Maybe the printed inductors have less coupling, although they are very close.

There's some more information below, in French. It's a very long link and I couldn't make it clickable here, so click on the link in the url below and then click download.

http://fr.groups.yahoo.com/group/ListeATV/message/7961

I heard back from Cimko. They are €8 in singles and they want a bank transfer - not very convenient. The price comes down for larger quantities of course. I've asked the BATC if they'd like to stock it in the shop.

Brian

g8cpf
Posts: 23
Joined: Thu Feb 28, 2013 8:09 pm

Re: Motorola MHW2723

Post by g8cpf » Thu Feb 28, 2013 8:16 pm

Have just "tamed" one of these on a home milled board (somewhat rough) and am getting 12watts out of it without too much increased IMD......Dont think I will run it quite that hard over a long period though.......

g8gtz
Posts: 1140
Joined: Wed Apr 07, 2010 6:26 pm

Re: Motorola MHW2723

Post by g8gtz » Fri Mar 01, 2013 11:49 am

Hi

Just agreed with Trevor that we will order 20 boards for the BATC shop.

Presume they will appear on the shop site when available but will post if I found out before then.

73

Noel

G4EWJ
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Joined: Wed Feb 17, 2010 10:11 am

Re: Motorola MHW2723

Post by G4EWJ » Fri Mar 01, 2013 1:24 pm

It must be getting quite warm on 12W at 18% efficiency. Good to know the IMD doesn't get too bad.

Brian

g8cpf
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Joined: Thu Feb 28, 2013 8:09 pm

Re: Motorola MHW2723

Post by g8cpf » Fri Mar 01, 2013 2:33 pm

It certainly would get warm if I didnt have it on a substantial heatsink, on which I intend to mount another, and to sum them to get decent power out......
At 8w out there seems to be no visible increase in IMD.....

73...de Mike in Minehead

G4EWJ
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Joined: Wed Feb 17, 2010 10:11 am

Re: Motorola MHW2723

Post by G4EWJ » Fri Mar 01, 2013 4:13 pm

Sounds very promising.

Brian

g8cpf
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Joined: Thu Feb 28, 2013 8:09 pm

Re: Motorola MHW2723

Post by g8cpf » Sat Mar 02, 2013 2:48 pm

BEWARE though.... Despite trying to make an "identical copy" of my first Amp, the second one proved much more difficult to tame..... in fact I blew it up by letting it oscillate too long.....Keep a watchful eye on your power meter with no drive applied !!..........Guess I just got lucky first time....Unusual for me :(

de Mike in Minehead

g8cpf
Posts: 23
Joined: Thu Feb 28, 2013 8:09 pm

Re: Motorola MHW2723

Post by g8cpf » Thu Mar 14, 2013 3:51 pm

Update on MHW2723 experiments......
Have re-milled boards for SMD components........very simple layout with no input or output lines ...pads only.
Used 10uH SMDs for all feeds except 12v to final amp, and NO decoupling caps adjacent to the module !..... (it is decoupled internally).
Now have two units, each producing a STABLE "5watts" of QPSK, as measured on a Bird Throughline.

Regards.... Mike in Minehead

G4EWJ
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Joined: Wed Feb 17, 2010 10:11 am

Re: Motorola MHW2723

Post by G4EWJ » Fri Mar 15, 2013 6:06 pm

Sounds good. Do you have a picture please.

Brian

g8cpf
Posts: 23
Joined: Thu Feb 28, 2013 8:09 pm

Re: Motorola MHW2723

Post by g8cpf » Sun Mar 17, 2013 9:27 am

[C:\Documents and Settings\Mike\My Documents\My Pictures\ATV][/datv 70cms]
Hope this is how one inserts pictures..... Not pretty, but it works......
Attachments
datv 70cms.jpg
datv 70cms.jpg (501.42 KiB) Viewed 5099 times

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