Benkson radios

[Neil Purling]

I believe that they are all imports from the Far East. The Benkson 323 under consideration is from Hong Kong. It has five of those totally anonymous black dome topped silicon transistors and a pair of Hitachi 2SB77's. I know Shango066 has a low opinion of those anonymous transistors.
I have no idea how old the creature is, though I am guessing around the mid 1970's.
Any chance of a circuit diagram anywhere?
I have a new battery holder on order before I can see if it has any issues I need to deal with.

[G6Tanuki]

Yes, Benkson was a "cheap and cheerful" Hong Kong import brand whose radios were sold by quite a few small 'independent' radio dealers as well as places like the Co-Op and Timothy Whites.

Many of them had cases that were made of a kind of grey high-density-cardboard, the outer surface of which was embossed with a black or tan faux-leather or crocodile-skin effect. Nothing special, I wouldn't go spending much money on restoring one unless it had some strange sentimental value.

[Neil Purling]

A Benkson 323 has a battery holder with a missing positive terminal & wire. I had no idea where to wire the positive to on the PCB. The switch on the volume pot operates on the negative side.
There is one single transformer that I am guessing is the driver & the output pair are a totem-pole.
Just like one of those Chinese kits........
Now then, in that there were two large 100uf electrolytics that serve as output coupler?? The other one is supply smoothing. I attacked the remains of a Chinese kit radio i'd binned for a battery terminal & wire.
A little soldering and a brief touch of the positive wire to the + leg of the capacitor brought forth a burst of Voulez-Vous by Abba.
A minor success story, but with a hefty dose of guesswork.

Expenditure: A packet of pound-shop AA's.

[Neil Purling]

I might have a look at the electrolytics, if I feel like it. It is somewhat quieter than I think it ought to be & that may be due to dried out capacitors. Thing is... New capacitors will probably cost more than the thing is worth that I would say as no more than £4. I'll have to look for a fly-tipped TV to quarry for electrolytics.

[Refugee]

I had a Benkson radio when I was a teenager. When it was new it had a flimsy vinyl sleeve that decayed rapidly. The white plastic case clicked open to gain access to the 4 AA cells that powered it.
It had the dome shaped silicon transistors in all positions with two larger ones in the output stage.

[kirstyd]

back in the late 60s /early 70s i had one of these and as a 13 year old mad about pop music it went everywhere with me .I saved all my pocket money and wages from a paper round to buy .As you can see in the photo it cost 30/shillings a small fortune to a school boy .It came from a shop that sold cheap furniture clocks and crap ornaments and those hideous pictures of Elvis Presley that seemed to move as you walked past them .Yes its a bit of cheap junk from Hong Kong but it was my best friend back then .I have fond memories of salvaging the big 12 inch speaker from a smashed up 50s radiogram [which wouldn't have been that old back in 1970] building a crude plywood cabinet from an old wardrobe for it and then plugging it into the headphone socket on the little pocket Tranny .and marvelling at how good it sounded so i thought .Lets face it anything would be an improvement on its little 2 inch speaker .It still works and every now and again i switch on and tune in to good old Medium wave

[emeritus]

Somewhere in the loft I still have my dad's Benkson pocket transistor radio dating from around 1961 that he used to use in the shed. It didn't sound too bad when played through an external speaker (Dad used to make up small extension speaker units from speakers reclaimed from old TVs and radios provided by our neighbour, who only wanted their scrap metal content). It used to eat PP3's, but he made up an extension lead using the snap connectors from some old batteries to allow the use of much bigger external 9V batteries. He later made up a 9V battery eliminator from a design published in one of the hobby mags that only used a bell transformer, one silicon diode, one zener diode, and a 1000µF electrolytic capacitor. I later fitted a jack socket to make a neater job of it. AFAIR it has a white plastic case with a gold metal grille, and is enclosed in an imitation leather case secured by snap fasteners, MW and LW only.

[camtechman]

It is somewhat quieter than I think it ought to be & that may be due to dried out capacitors.

Quite often, not only with the Benkson brand but with other brands of that type, the capacitor that links the wiper of the volume control (middle contact) to the first transistor in the amplifier stage goes duff and reduces the volume.

This can be a small value electrolytic or a ceramic type.

[Neil Purling]

That Satelite looks very much like the Benkson, but the Benkson has a dial like a watch.
What I can see of the speaker grille is the same too and even the same rubbishy case. The one of the Benkson is horribly stiff and is splitting. It offers little protection to the radio.

I know several places that are hot-spots for fly-tipping. I will have a look and see if I can harvest any TV's for panels to strip of re-usable electrolytic capacitors.

[Refugee]

I do not have my old Benkson any more but from a crate of basket cases I retrieved one that is almost the same. It still has the vinyl jacket but it does not have an internet connection even though the brand name might mislead you into thinking it should have one

[Radio tirana]

Hi Refugee Great to see another one of these has survived.
I also have an Internet Ten in my shed still working after 45 years I think I was 12 when I received it as a Christmas present.
I used to use it under my pillow to listen to Radio luxembourg or Radio 4 when I was supposed to be asleep. I can't bring myself to dispose of it.

Radio Tirana

[Neil Purling]

The Internet 10 is also very much like the Benkson 323. I wonder if there is a common origin?
Refugee: What model was your Benkson. Mine looks like cr*p to put it bluntly, exactly as if it was sentenced to life in the shed. Most of the chrome finish on the front is absent
The vinyl case is hardened. They used to love that stuff in the 70s. I like the Internet 10 case better! Even if it is fake leather (looks like cardboard).
How about some pictures of the inside of the Internet 10? The guts seem to vary a bit.

[Refugee]

The Benkson I had got wrecked by another teenager when I was at school and the model number is long forgotten.
The internet 10 had broken aerial wires due to the batteries getting loose I think. The reception is about the same as the Benkson I used to have.

[Neil Purling]

How much 'slack' is there on the values of electrolytics in a radio like this Benkson?

I have been component shopping - with pliers and a Warrington Hammer in Flytip Components PLC. Every town has probably got a branch

[Refugee]

Last year I liberated a little audio isolation transformer from a dumped toy taxi radio.
Dumping space is free if there ia an old fridge or Dyson present.

[short wave]

In the 80s a firm i worked for got a lot of components off a Benkson importer.

[Neil Purling]

Dumping space is free if there is an old fridge or Dyson present
Any dumped electronic appliance on it's own is fair game.
Cleaners are good if you want a long length of flex.

Back to the subject in question... I have been bridging various electrolytics without noticeable improvement. I am wondering if the problem is in the IF strip? Might try replacing those dome-top silicon transistors.

[julie_m]

Be careful leaving anything behind, though, lest you be erroneously blamed for dumping it. Post hoc ergo propter hoc, you touched it last so it's your fault. (Literally: After it so because of it.)

[Neil Purling]

Have many of you had issues with those dome-topped black encapsulated transistors. I assume they are silicon devices, I don't know what the case style is called
Some of those in the Benkson are completely un-marked. Why?
The YouTube guy Shango066 doesn't really like them. I was wondering if it was likely that these un-marked devices are rejects.

[Refugee]

I have had a couple of dome topped 2N3819s that were sort of faulty and the circuit was better with new ones.
I have also seen a BC108 in the same package.
I might have a few in a tin of old transistors. I will have a look next time I am in the workshop.