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 Icom IC-701
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 Return to top of page · Post #: 1 · Written at 5:57:24 PM on 21 November 2018.
Flukeoneseventyfive's Gravatar
 Location: Laidley, QLD
 Member since 16 September 2015
 Member #: 1799
 Postcount: 79

G'Day Folks.
Went to the Gold Coast ham fest a week or so back.
Wasn't as many sellers as normal.
But I managed to pickup two old, well they are these days, from around the late 1970's to early 1980's, a Yaesu FT-290R Mk2 with the 25watt amp for $30.00
wasn't sure if it was working or not, But got it home gave it a clean up and a quick check over and slowly bought the power up on initial start up.
Greeted with the cw beacon from one of the Chinese cube satellites.
very hot front end on the receiver, I haven't checked, but assume a mutek board is fitted.
only issue is the steps on FM are 12.5 and 25kHz, will have to do the mod to get at least 5kHz steps for FM use on the satellites.

So the other purchase was an Icom IC-701, which has issues with the band switch relay and diver board, caps for the multivibrator circuit that drives the switch.
It cost me $50.00, which looks like it will be a pain, but something interesting to work on.
has been people though it before, the vfo works and the display is fine, no rx/tx or audio at the moment.

and I picked up an old 14 element 1296 MHz yagi, some new satellites going up soon, with 23 cm up link, I checked the return loss on the antenna, with the antenna analysler and it is very flat from 1260 to 1300 MHz, so will be very usefull.

There was also a couple of bakelite radios I picked up, a mickey and a westinghouse.
any pointers on the ic-701, it is a boat anchor now, so I could tie a rope to it and hoist it into the dam, but still have no water in the dam yet.
The drought has broken, but still need more rain...
Cheers
Peter......


 
 Return to top of page · Post #: 2 · Written at 7:44:47 PM on 21 November 2018.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 4725

IMO, Icom gear is worth fixing.

The original instruction manual is available for download on numerous sites, including the Icom Japan website.


 
 Return to top of page · Post #: 3 · Written at 4:43:32 AM on 22 November 2018.
Flukeoneseventyfive's Gravatar
 Location: Laidley, QLD
 Member since 16 September 2015
 Member #: 1799
 Postcount: 79

G'Day GTC.

I found one site with hi-res scans, much better on the eyes.
I stripped and cleaned the switch for the band pass filters, I have to see if the multivibrator circuit is working, two electro caps in the circuit, look suspect, I didn't have any that physical size in the value to replace, but will get that section of the radio working first.
at least the PLL and all the LSI devices appear to be functioning, the Display and VFO are working, so it makes it worth proceeding with the repairs.

I haven't look at the through hole rivet, issues and poor soldering, that plagued these models.

Always wanted a 701 when they first came out, tad too expensive, for me at the time, second hand ts-520 with digital display worked for me. then the ft-707 and a ts-940, still have them apart from the ft-707.

Getting great signals on 20 meters from/to the UK in the evenings at the moment.


 
 Return to top of page · Post #: 4 · Written at 7:31:50 AM on 22 November 2018.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 4725

This one?

http://jvgavila.com/man_ham/ic701/ic701.htm

I was just reading about that through hole thing here: http://www.angelfire.com/biz2/mts/Oldies.html

Sounds like a lot of work I must say. I gather the 701 listed at US$1,600 in 1979, which is about US$5,700 today.


 
 Return to top of page · Post #: 5 · Written at 10:42:24 AM on 22 November 2018.
Flukeoneseventyfive's Gravatar
 Location: Laidley, QLD
 Member since 16 September 2015
 Member #: 1799
 Postcount: 79

Spot on GTC, that was the site.
There is some info around, But I think the bulk of it is in printed form, regarding the issues on the 701, and has not made it to the internet.


 
 Return to top of page · Post #: 6 · Written at 10:58:50 AM on 22 November 2018.
Flukeoneseventyfive's Gravatar
 Location: Laidley, QLD
 Member since 16 September 2015
 Member #: 1799
 Postcount: 79

 
 Return to top of page · Post #: 7 · Written at 10:50:53 AM on 6 December 2018.
Flukeoneseventyfive's Gravatar
 Location: Laidley, QLD
 Member since 16 September 2015
 Member #: 1799
 Postcount: 79

An update on the 701.
Bit of a pain to work on, but I found the 9 volt regulator circuit was faulty, one transistor was loose in two of the soldered pads, and there was a few other similar issues, reflowed the suspect ones I could see.
Replaced a burnt resistor in the collector of the output transistor or the regulator circuit.
That , now had the receiver circuit working.
I had stripped and cleaned the Ledex switch for the band pass circuits, I had t replace the two electro's in the mutlivibrator circuit that drives the Ledex switch, which now appears to want to change when the band switch is rotated, it needs a bit of a helping hand, though, most of time to rotate.
I will run the receivert through an alignment first up and then see what we can do to get the Ledex switch to function correctly.
Then onto the transmit side.
As it is I does very well on 20 meters Receive, with a lot of European and Asia stations, only the very strong local stations will move the S meter and the AGC doesn't appear to work like it should.

I has been great to get it working to this stage, I seen a Kenwood TH-d700a on ebay and managed to get it for $36.00
It was for parts not working and had no controller head.
Worked out well as I had the head, but a dead d700 that I haven't been able to repair.
But this one arrived and I powered it up, with the head.
No signs of life, popped the bonnet and a few voltage measurements, pointed to the surface mount fuse, that powers the remote head.
Replaced the fuse and it's working very well, but I will run it through an alignment after a reset.
With the large number of new amateur radio satellites just launched, it will be getting a bit of a workout.


 
 Return to top of page · Post #: 8 · Written at 4:35:50 PM on 6 December 2018.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 380

Hi, interesting read, bit out of my interest, but gee talk about things being discarded with little wrong with them.
Makes you wonder about whole TV's being dumped outside houses, the next time I see one I might grab it and see if a surface mount fuse is involved!
Keep posting as you fix things always interesting to see people doing things.
Fred.


 
 Return to top of page · Post #: 9 · Written at 10:12:08 PM on 6 December 2018.
Frank F's Gravatar
 Location: Brunswick, VIC
 Member since 3 May 2017
 Member #: 2100
 Postcount: 31

Hi Fred,

That is called built in obsolescence.

My TV blew one of those surface mounted fuses a few years back. Worked as a monitor but the tuner was dead. I got a copy of the circuit and couldn't figure out why a fuse was fitted after a current limited and thermally protected voltage regulator. A wire link was fitted and the TV is still working great.

Regards, Frank.


 
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