HW-7 REPAIR - July 12th 2014
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I am a bit of a hoarder. I buy things at flea markets and keep them around here in my basement at my house up in Elliot Lake. Gives me something
to do because I took early retirement. I putter around down the basement in my shop and listen to the ham conversations on the radio. Mostly on
20 meters but (lately) Ive started listening on 18 mhz (using an IC718). Nice band 18 mhz (17 meters).
ANYWAYS.. I have some extra parts and parts boards for rigs like the HW-7. A fellow up in VE8 land sent me an HW-7 to work on and some of
these parts came in handy.

First.. I'd like to say that I don't go hard on people when it comes to repairs. My shop rate is $10 per hour and I often cap the repair at a sensible
amount because it might run too expensive otherwise. I enjoy doing the repairs and I REPAIR OLDER SOLID STATE GEAR that I ABSOLUTELY
KNOW I CAN REPAIR and I have parts for.

Often..these are sentimental pieces that (if they weren't of sentimental value) they might not get repaired at all.
The receiver of the HW-7 is pretty
basic.

Two active components. There is the
dual gate mosfet (type 40673) and
then there is the high gain CA3035
(pictured left) op amp type audio
amplifier.

I ordered in some CA3035s for my
shop because I have some HW7s of
my own and I want to have spares on
hand for any repairs that might come
in.

The CA3035s I ordered in ..did not
have the formed leads so I carefully
formed them with a pair of needle-nose
pliers..
Above pictured. I turned the rig over and
formed the leads to match up with the
holes in the circuit board.

Then plugged in the new U1 audio
amplifier and soldered in the circuit and
the receiver now worked!

I also tested the Dual Gate Mosfet and
tested it with my circuit and found the dual
gate mosfet to be ok.


Pictured left.. the broken 40 meter
doubler coil. I did not try to do a repair on
the coil..but rather I just replaced it
because I had a spare off my parts board.

The CA3035 is about $13.00 cost to me
plus $4 shipping..but  I ordered some
more in at the same time to moderate the
shipping cost.
To the customer I charged $16 for this
part. (They aren't cheap)! The used coil I
charged $2 Labour $15.
SO HERE IS THE COST TO THE CUSTOMER:

To the customer I charged $16 for the CA3035  (They aren't cheap)!  The used coil I charged $2 Labour $15. So total cost parts and labour $33.00

Which isnt too bad actually. The HW7 used to sell for about $99 or so up here in Canada in 1973. It was a kit that Heathkit Electronics offered.

SO THIS IS A GOOD EXAMPLE OF MY REPAIR PHILOSOPHY! - THE BIG COST OF THE PROCESS IS THE SHIPPING. It would probably cost about
$22 each way shipped in Canada or USA. (IF YOU CONTACT ME (email
earlinclayton@yahoo.com) I can give you an estimate on the postage and
an estimate on the planned repair you want to do.

Another option: meet me in person at ONE OF THE OTTAWA AREA FLEA MARKETS (May in Smiths Falls or early September in CARP near Ottawa).
YOU can arrange for me to pick up a rig for repair and save at least one way in the cost of shipping.