advertisement


what really happened during the late 70s early 80s in the hifi press

Jim Audiomisc said:
This shows the topside of the L15 decoder board. Annoyingly, I don't have a photo of the track side, nor a diagram! Wish I had. However I think it was essentially what was on the TI datasheets.

http://jcgl.orpheusweb.co.uk/temp/L15pic.jpeg

I can't recall when, but I think some 600s used some soft 'plastic washers' that took the place of mica insulators + heatsink compound. The idea being that they were soft enough to act as both. The were opaque. But I have no idea how they might have aged over this many decades!
Click to expand...

The same MPX filter appears to have been used again then but it's a completely different board to the RCA decoder equipped one.

I'll have to give the OPT mounting a proper once over when I do the rest...
 
Jim Audiomisc said:
WRT the 400 range. The problem was that the finish for the fascia tended to be quite uneven, so in the shop or on show looked cheap and tatty. Not easy to sell, particularly to a skeptical spouse! In essence the 500 was a rebranded 400 and sold like hot cakes.

Personally, I think the 600 range was one of the best styled audio units ever designed and sold. Can say that because I had nothing to do with the external design. The snag was the impact on transformer and heatsink sizes. And led Ted to put the output devices well out of thermal contact with what drove them. Shame heatpipes weren't around when it was developed.
Click to expand...

Aha... I'd noticed the electronics seemed to be pretty much unchanged from 400 to 500 series yes, and wondered why a new but the same range was released! I've only seen pictures of the 400 range but really liked what I saw!
Not so with the 500 range which looks "1970's teak and everything was a shade of brown" if you know what I mean...

I have a 500 series FM tuner actually and it is black, a rather nice gloss black that can almost pass for piano lacquered from a few feet away. I don't know if they were available like this or it was refinished by a past owner.
I have a memory of having 2 of these in fact, the other in normal wood finish. This one vanished.... like an old oak table:D

Yep the 600 series was great styling. I thought it worked much better with the receivers than the amps or tuners where the greater width makes them look more slim line.
Conversely with their Leak rivals from the Delta range I loved the look of the amps (no one seems to share my love for the styling of these!) but the Delta 75 receiver just looks wrong... "awkward" if you like...
 
Arkless Electronics said:
The same MPX filter appears to have been used again then but it's a completely different board to the RCA decoder equipped one.
Click to expand...

That chimes with my recollection that I'd changed to the TOKO filters before replacing the old RCA chip with the TI one. Alas, when I left the factory I took my notes on the 700, but nothing much on earlier models as it was assumed there would be no need for any mods to them, etc.
 
Arkless Electronics said:
The same MPX filter appears to have been used again then but it's a completely different board to the RCA decoder equipped one.
Click to expand...
That looks like the contents of the Toko MPX filter I bought from Ambit 35 years ago. I think that this was the standard part for most of the chips.

edit
I always wonder how much better these tuners would have worked with a two layer PCB with a ground plane. Jumper links just don't work well at 10.7 MHz or VHF
 
Arkless Electronics said:
I have a 500 series FM tuner actually and it is black, a rather nice gloss black that can almost pass for piano lacquered from a few feet away. I don't know if they were available like this or it was refinished by a past owner.
I have a memory of having 2 of these in fact, the other in normal wood finish. This one vanished.... like an old oak table:D
Click to expand...

No idea on that. Armstrong did make 'specials' on occasion for someone who paid for it. But just as likely to be an owner with some suitable DIY skills. That was an era when some users made their own 'radiograms' and cabinets, etc. Reminds me that this is another example of the kind of thing that used to appear regularly in HFN but doesn't nowdays. DIY speakers and even turntables/arms sometimes with full sets of drawings!
 
davidsrsb said:
That looks like the contents of the Toko MPX filter I bought from Ambit 35 years ago. I think that this was the standard part for most of the chips.
Click to expand...

Yes, I think the only change was to not have the lid so it would fit the space! In modern RFI terms that may seem crazy. But all the RF/IF of the tuners was also open!

The 600s looked sleek because of the black tray that made it seem shallower and floating above its shadow. The eye judges by the fascia depth and tends to ignore the tray under it. Neat trick.

Alas, HiFi was swamped by silver boxes, then black ones. Boring, boring, boring.
 
davidsrsb said:
That looks like the contents of the Toko MPX filter I bought from Ambit 35 years ago. I think that this was the standard part for most of the chips.

edit
I always wonder how much better these tuners would have worked with a two layer PCB with a ground plane. Jumper links just don't work well at 10.7 MHz or VHF
Click to expand...

if you look at the front end of the 600 FM tuner you can see that the input from the antenna doesn't seem to be connected to anything much. 8-] There is a coil, beside a metal screen, with another coil *the other side of the screen*.

Ted fitted the screen because the overload level was too low in early versions 8-]
 
davidsrsb said:
That looks like the contents of the Toko MPX filter I bought from Ambit 35 years ago. I think that this was the standard part for most of the chips.

edit
I always wonder how much better these tuners would have worked with a two layer PCB with a ground plane. Jumper links just don't work well at 10.7 MHz or VHF
Click to expand...

I wouldn't expect any appreciable difference. 10.7MHz no problem and even VHF perfectly doable with well laid out single sided boards. The decoder board of course is at audio frequencies, plus 19, 38 and sometimes 76KHz.
 
Jim Audiomisc said:
if you look at the front end of the 600 FM tuner you can see that the input from the antenna doesn't seem to be connected to anything much. 8-] There is a coil, beside a metal screen, with another coil *the other side of the screen*.

Ted fitted the screen because the overload level was too low in early versions 8-]
Click to expand...

Hmm! Rather seems to obviate the need for the RF amp!
 
chartz said:
All these are totally unheard of across the Channel.
Did they ever sell elsewhere?
Click to expand...

That surprises me! They were quite big by UK standards and I recall ads boasting of their export success... especially one with a group of Japanese holding a receiver and the ad saying that the Japanese couldn't get enough of them and loved the advanced technology!
 
I couldn’t find any ads or perhaps late product reviews in my 40 year-old French magazine collection (started in the late 70’s).
I never saw any on dealers’ shelves either, or second-hand in local ads.
The ad with the Japanese was B&O, wasn’t it?
 
chartz said:
I couldn’t find any ads or perhaps late product reviews in my 40 year-old French magazine collection (started in the late 70’s).
I never saw any on dealers’ shelves either, or second-hand in local ads.
The ad with the Japanese was B&O, wasn’t it?
Click to expand...

There may have been a similar B & O ad I guess.... The Armstrong ad had a group of Japanese blokes in suits and either it was on a table or one of them was holding it and the rest were gathered around it pointing at it with admiring glances
 
Interestingly the A & R A60 was roughly the same price as the Armstrong 621 amp in 1978.. direct competitors!

In 1974 the rival Leak Delta 75 was a fair bit more expensive than the 626... £164 to £132

The Delta 75 can also be recommended to anyone looking for a '70's British receiver. Whilst pretty much the Delta FM and Delta 70 amp in one unit, it came out several years after the amp and tuner and quite a few upgrades and afterthoughts are Incorporated which make the receiver significantly better than the tuner and amp!
 
chartz said:
All these are totally unheard of across the Channel.
Did they ever sell elsewhere?
Click to expand...

Yes, but in general the export-import costs made the price higher.

A 600 got a good review in a Dutch magazine. Good enough that Armstrong used reprints as part of their publicity. A 625 also got a remarkably positive review in the March 78 issue of "Audio" in the USA that thought it sounded absolutely superb.

600 sets were also exported to various other countries. I recall that we used to get a crate of oranges delivered to the factory just before Christmas from the Israeli importer! Everyone got some oranges to go with the chickens Armstrong gave staff as xmas gifts. (Great firm to work for.)

I can also recall Alex Grant regrettinf exporting to an African country as we never got paid! And one shipment had a fork-lift truck skewer the packing case, smashing sets inside.

As the mags concerned are now no longer going maybe I should put copies of some of the reviews up on the web.
 
You must log in or register to reply here.


advertisement


Back
Top