Sony ICF-SW7600GR Multi Band World Receiver Radio: Who cares about DX listening?

[jebem]

An icon among the amateur radio...

This morning I got this new baby into my radio collection.
Saw it for sale with an 69 Euro price tag. Good working condition, but the accessories are missing (no antenna, no pouch, and no manual).

The seller wouldn't lower the price, but after bargain for a while, I finally got it for 65 Euros.
If I had the required patience, probably I could find it for a better price.
But this one was an impulse buy. I just had to have it!







As usual, I like to inspect the interior of my new acquired equipments whenever possible.
I want to find out if the equipment is still using the original parts, or if it was repaired or modified by the previous owners.
It happens that this one was in pristine condition. Probably never opened before me.

Step by step disassembly.

Remove the 5 star screws in the back.
The back and front covers are free to be removed by gently push the four plastic claws on the back cover.

The chassis - back side.



The chassis - front side.
The plastic keyboard key assembly was removed by pulling it out, leaving the key switches visible.



The chassis - front side detail.
Back supply capacitor: 2200uF / 5.5V. It is enough to maintain the clock operation for at least one minute when it is time to replace the four in series AA depleted batteries.

[jebem]

Step by step disassembly (cont.)

The 8 Ohm / 0.5Watt Loudspeaker removed and terminal wires unsoldered.
It is secured by two plastic claws.



Key Board assembly removed from the front side of the plastic chassis frame.
The board is secured by two plastic claws.
Gently pull the flat cable from the connector.



Plastic chassis frame - Front side ( Key Board assembly was removed).
The flat cable interconnecting the Main board and the Key Board is visible in the central zone.



Plastic chassis frame - Back side ( Key Board and Main Board assemblies were removed).
The four wires of the ferrite antenna were unsoldered from the Main Board.



Main Board assembly removed from the back side of the plastic chassis frame.
It is secured in place by four plastic claws. Push them gently to remove the board.



Main Board assembly detail - right side.
"X201" 55.390MHz AM OSC2 crystal visible in the central zone.
"IC203" CXA1522 Pre/Power audio amplifier IC in central bottom zone.



Main Board assembly detail - left side.



Exploded view.




After reassembling, the radio worked as nicely as before
I use a RF signal generator to do the checking. While it miss a graduated attenuator knob because it is not a professional calibration equipment, it is good enough for my needs.

[rprosperi]

(07-12-2015 05:15 PM)jebem Wrote:  As usual, I like to inspect the interior of my new acquired equipments whenever possible.
I want to find out if the equipment is still using the original parts, or if it was repaired or modified by the previous owners.

Please remind me to never park my car in your neighborhood...

As usual, nice teardown details with great photos. I know and care nothing about radio equipment, but I still find these teardowns interesting. Guess it's the engineer in me wanting to know how things work.

Here is the important question: Once reassembled, how many small screws were left? Be honest...

[Bill (Smithville NJ)]

(07-12-2015 05:15 PM)jebem Wrote:  Who cares about DX listening?

I do! I do! Or I should say I used to do a lot of Shortwave listening. Back when there were a lot of international broadcasters - before they shut most of them down and went to the internet. I still do DXing, but it's with my ham radio.

Great to see the Sony radio along with your excellent disassembly photos.

The 7600 series was a best seller. Over the years I've had the original ICF-7600 Analog, ICF-7600D (ICF-2002 in North America) and the ICF-SW7600GR.

My favorite Sony radio was the ICF-2010. A little bigger, but a great radio.

A few years ago, I decided to go back to "old school and picked up a couple of Panasonic RF-2200 Analog radios. These are about the size of a lunch box, and have great receivers for their day.

73, WD9EQD
Bill
Smithville, NJ

[jebem]

(07-12-2015 06:13 PM)rprosperi Wrote:  Please remind me to never park my car in your neighborhood...

Hehehe... No worries, I do not do cars anymore, since my last rebuild in 1976 on my Alfa Romeo Giulietta 1300.

I would bought this car second hand from a friend that used to do rally with it.
As the engine had no power enough for my needs at the time, I decided to dismantle it piece by piece to have a look.
After 6 months I was trying to find out were was the problem, until another friend of mine, a engineer working at Renault, gave me an hand and the verdict was final:
The engine state was beyond any hope of recovery.

So we went for shopping around on scrap dealers and found a nice 110HP 1600cc engine for sell.
To make a long story short, the car gave me many miles of satisfaction and I have learned quite a few things about mechanical engineering in the process.

To put this story into perspective, it happened in Africa, Mozambique, a couple of years after the independence from Portugal, at a time when the goods where scarce in a country that was trying to rebuild almost from scratch and facing a civil war at the same time, and where cars were mysteriously disappearing overnight only to be found a few days later in pieces for sell, guess where: in the scrap dealers!

(07-12-2015 06:13 PM)rprosperi Wrote:  Here is the important question: Once reassembled, how many small screws were left? Be honest...

You got me, I have to confess that I keep a large box full of screws in my basement that I have absolutely no idea from where each one came from.

But in this case, the SONY SW7600GR is really well designed and built, and it only uses 5 large screws. I wouldn't miss it even if I try hard

[Paul Berger (Canada)]

(07-12-2015 05:15 PM)jebem Wrote:  Who cares about DX listening?

I still do occasionally, I have a couple Grundig radios a YB500 and a Satellit 700. I also have an old Radio Shack receiver, probably one of the first they sold with a digital indicator, I think they thought big was impressive at the time as it is in a large mostly empty case.

Paul.

[jebem]

(07-12-2015 08:17 PM)Bill (Smithville NJ) Wrote:  

(07-12-2015 05:15 PM)jebem Wrote:  Who cares about DX listening?

I do! I do!
(...)
A few years ago, I decided to go back to "old school and picked up a couple of Panasonic RF-2200 Analog radios.

73, WD9EQD
Bill
Smithville, NJ

Thanks for sharing, Bill!
I knew at least one member here should have been into DXing.

I never was into serious amateur radio and never took the license, probably because I stared my professional work on telecommunications in 1975, working for RACAL, a large company at the time in South Africa with a manufacturing plant and technical support branch in Mozambique.

Once, in 1978, I was repairing a high power, short wave, long distance military RCA triodes tube equipped transmitter in the Niassa lake Metangula military naval base.
The power supply transformer was damaged and had to be rewind. I was there to install it and make sure the communications could be re-established to Maputo (about 2000Km away).

After the usual preparation steps, which included the pressurization of the transmission line, tuning all the pre-stages for minimum current and then fire up the output push-pull stage, checked the SWR ratios, I went decidedly to the morse key and started keying frenetically to see if the equipment could cope with the requirements.

Only then I realized that something was wrong.
All the personnel in the communication room (all of them Morse experts that used to do championships to see how fast they could send and decode messages) were looking to me with inquisitive faces.

And one of them, just asked me:
Comrade Mesquita, what the hell are you transmitting and to whom???

I had to explain that I didn't learn Morse properly and I was just doing my job at the electronics level.
I'm not a spy, honest!

But I still have a couple of radios from that era, that we used to listen to soccer matches broadcasted from Europe to whole world:
One National Panasonic RF-2800B and another Grundig Satellite 6001.
Both of them are stored away for more than 30 years in my parents home in North.
One of these days I will have to rescue them and see how good they were.

[jebem]

(07-12-2015 10:43 PM)Paul Berger (Canada) Wrote:  

(07-12-2015 05:15 PM)jebem Wrote:  Who cares about DX listening?

I still do occasionally, I have a couple Grundig radios a YB500 and a Satellit 700.

Thanks, Paul, for sharing.
I have worked for Grundig in Mozambique as well at JFS company (Joao Ferreira dos Santos), a very well respected holding company even after Mozambique independence in 1975.

Grundig was very strong as a brand, with excellent products at the time.
The YB500 and the Satellit 700 are newer generations. In my time most systems were basically analog, no digital PLL's or fancy digital dials.
I remember very well the Satellit 6001 (I still have one in my possession), despite being a consumer oriented product, it was a very strong competitor at the amateur radio as well.

[Bill (Smithville NJ)]

Back when I was doing a lot of DX listening on the shortwave bands, the best part was collecting the colorful QSL Cards.

Following are a few I collected back in 1972:

   
   
   
   
   


Bill
Smithville, NJ

[vk6ti]

Hi jebem,
Nice breakdown, your next mission is to acquire an old tube (valve) receiver
(boat anchor), and start pulling that apart. Make sure you have a solid bench
for it to sit it on.?
Ray

[jebem]

(07-13-2015 07:20 PM)Bill (Smithville NJ) Wrote:  Back when I was doing a lot of DX listening on the shortwave bands, the best part was collecting the colorful QSL Cards.

Bill
Smithville, NJ

Thanks for sharing!
Nice RSA card!

Jose Mesquita
Lisbon

[jebem]

(07-13-2015 10:58 PM)vk6ti Wrote:  Hi jebem,
Nice breakdown, your next mission is to acquire an old tube (valve) receiver
(boat anchor), and start pulling that apart. Make sure you have a solid bench
for it to sit it on.?
Ray

Hi, Ray!
Guess what, valve equipment (or tubes, depending on the culture) is another of my hobbies along with transistor radios and calculators.

Back in the day, when working at Conrad Maputo (Lourenço Marques), I use to repair an maintain military and marine professional equipments like VHF and HF transmitters and navigation systems (Radar, Sonar, etc.) from different brands like DECCA, REDIFON, FURUNO, RACAL, STORNO, RCA, etc..

Many of these systems still used tube devices, specially on marine transmitters, and some used hardwired assemblage, like some REDIFON's !

Some photos from those early days of my professional life.
I'm the second from the right.
And my ID card at the time (two years after Mozambique independence, we still used the old colonial ID cards....).

[Les Bell]

(07-13-2015 10:58 PM)vk6ti Wrote:  your next mission is to acquire an old tube (valve) receiver
(boat anchor), and start pulling that apart. Make sure you have a solid bench
for it to sit it on.?

Ray, your comment spurred me to take a look at what might still be around - and lo and behold, what should I find on eBay.com.au but a Trio 9R-59D, the radio that started me off back in 1970 or thereabouts. I thought it might be kinda nice to have, for sentimental reasons, but the auction finished a few minutes ago and the radio went for $A270.75 - unfortunately, my wallet isn't that sentimental!

Back when I was G(M)4CFM, I had a KW-2000E, which I brought to Australia, but I never bothered getting the VK2 licence. Too busy, then and now, unfortunately. In fact, looking around the place, I wouldn't have anywhere to set that 9R-59D, let alone time to use it.

[vk6ti]

Hi Jebem / Les
Sounds like we would have a good time over a couple of beers.
I spent much time fixing valve gear inc transmitter, receivers, and music equipment, and still have most of my parts and equipment, but
not enough time to play with HT+ much, and as you mentioned Les, it
Is getting pricey. (as is some HP gear)
I also go for real old triodes, transistor radios, and of course HP calcs.
Along with all things exothermic

Cheers for now
Ray

[Sukiari]

What a steal! I've had my eyes peeled for one of these at a reasonable price for years. I'm a ham and of course have GAS for nice radios.

How is it for AMDX?

DE K7ATR

[jebem]

(07-22-2015 06:04 PM)Sukiari Wrote:  What a steal! I've had my eyes peeled for one of these at a reasonable price for years. I'm a ham and of course have GAS for nice radios.

How is it for AMDX?

DE K7ATR

Yap, I was kind of lucky, despite we can see this model for sell at similar prices + s&h on eBay.

The thing is that the guy who sold it to me was aware of its value, as he told me that "the radio was worth around 200 Euro when new".
My guess is that he just wanted to get rid of it as probably he believed the radio was faulty in the AM bands as it is mostly able to receive noise when using the fixed telescopic antenna.

In fact our area around here (Lisbon) is polluted with a lot of RF noise coming from different sources, like some telemetry systems installed in the home electrical energy counters and mainly from the Cable TV distribution network.
Most people are not aware of this because this strong RF noise is filtered out in the 100MHz VHF FM band where people listens to analog FM radios (yes, we still use it here).
But when you try to listen to AM you will have this strong noise that makes impossible to receive medium or weak stations using just an internal antenna.

AM DX... I confess that I spent a few hours at night the other day tuning to Spanish and a few Arabian stations (so, no more than 300 or 400 Km away from me) but this interference noise is everywhere taking out all the fun.

I have other radios and all of them have the same issue with this RF pollution.
Like this beast from Latvia when it was USSR:






This is a rare USSR domestic limited edition (as far as I know) MRP Model 103 "50 years USSR", based on the popular but expensive Rīga 103-2 Radio made in Riga Popov Radiotechnika Works plant, Latvia.

Why?

Because the USSR ordered Riga plant to manufacture a special 50th anniversary of the USSR foundation (1922) edition, to be offered in 1972 as a special gift to the members of the Supreme Soviet!

This special edition has no indication of the original Riga ("RRR") manufacturing plant anywhere outside or inside.
On the back the brand name is just "МРП модель 103" and in front it sports the label "50 лет СССР".

Now, a quick search in Google shows us that the Supreme Soviet never had more than (750 x 3) deputies, so this domestic limited edition would be restricted to maybe a maximum of 3000 units, considering QC issues and a small reserve to be used when needed.

Another gift option with the image of a silhouette of Riga was also manufactured to be offered to the foreign guests attending the ceremony.

This radio is in fact a Riga 103-2 series and it was a expensive first class equipment to own in USSR at the time.
However this special edition sports the USSR flag and the 50 Years USSR inscription using fine quality woods and workmanship. There is no painting here, just natural wood and lacquer to finish it.

Notes:
"МРП (Министерство Радиотехнической Промышленности)" = MRP (Ministry of radio technical industry).
"50 лет СССР" = 50 years of USSR.
"МРП модель 103" = MRP model 103.