Identifying unknown items

[Julesomega]

Thanks for the replies to the last two items. I've yet to look at the transformer for those Joules because I'm still falling over myself trying to identify Unknown Items

I hadn't even thought to look for a date on the vibrator supply as I assumed it would be a WWII item and that someone would immediately recognise it, but I've looked again more closely and the vibrators are clearly marked "Mallory 629C 6 Volt" which answers the questions about DC input and confirms that it is non-synchronous. The transformer underneath is for the vibrator outputs, which leaves the smoothing choke on the top side plus two large RF chokes and two air-wound RFCs underneath.

It does therefore not have an LT output, leaving the question about the HT o-p

Can't see any dates, but there may be one on the block capacitors which can only be removed by a major dismantling of the case which is held together with BA screws with pressed flat nuts locked with varnish, and which suggests very expedient wartime production in a hurry

but not yet competing with the power of a xenon discharge tube

Even my new "compact" camera (Fuji x100V) has a Xenon flash tube. Very high peak power.

[Julesomega]

I've just found a couple of little securing or positioning pieces which I feel came out of something, most likely a comms rx. Anyone know?

[Julesomega]

Forgot to say, it's mild steel tapped M5, so not Vintage

[Radio Wrangler]

It looks like a little weld-on stud which must have dropped off something.

There are machines called stud welders which force studs against panels and apply a jolly good burst of current to form a spot weld. Mostly these things have male or female threads in line with the axis of a round stud, but some have holes at right angles so they can be used as a surface for a lid or another panel to be screwed down to. These are alternatives to bending tabs inwards, drilling and tapping them. There are also little clevises designed to straddle an edge of a panel fitted into a notch in the panel and held by a rivet through it and the panel. The end of the clevis has a male or female thread to allow a lid to be attached. The weld-on ones get used where you don't want a clevis and rivet showing.

Weld-on studs can be troublesome because spot welds aren't 100% certain. Some drop off sooner or later.

Friction weld ones (inevitably round) are spun at high speed and then forced into a panel. Friction heating makes metal flow and the pressure forces metal in almost liquid state outwards from the joint, carrying out surface oxide and contamination. You get noticeable flash from these things. The rotating part is driven through a fast acting clutch and is allowed to stop quickly when the joint forms.

A lot of later HP equipment had front panels with an inner structural panel, covered by a dress panel with holes for buttons, controls, meters etc and which was painted and silk screened with labelling. The rear of the aluminium dress panel had aluminium threaded studs welded on. At first electric welds, then later friction welds. This had to be done well enough that the cosmetic side of the dress panel was smooth enough to take paint and silk screen and show no markings from stud attachment. Shall we just say manufacturing didn't find it easy?

David

[Julesomega]

Holding panels sounds good. Anyway, I've only got one now, the other one was camera-shy, and even two is not that useful, but I just wondered

Now, two more items to identify: I'm going through the transformer boxes and wondered what these are. There is a nice grey smoothing choke, "Admiralty Pattern 6077A, 9H 100mA, most likely from a receiver, but which one?

There is what I take to be an audio tfmr, it's the wrong shape for mains: it has three windings and only "271C" to identify it. Might even have come from a SWB 8

[Julesomega]

Okay I know what this is - it's marked on it: "Farnell FT1 Sound Sync Indicator" - but what's it supposed to do?

It runs off a PP9, has a 6-pin DIN plug on a flying lead, and phono sockets on the front marked "VAR IN" and "REF IN". What sort of Various Variable might this be? There's a big knob for some sort of amplitude, and on the rear it can be switched to 1 or 2

It appears never to have been opened, not even for fitting a battery; no doubt someone thought it was worth ordering one but when they hit the ON switch nothing happened so it went back into stores. How do you usually synchronise sound and vision?

[Julesomega]

No enthusiasts for home video-making in the 70s? Never mind, here's something definitely Vintage Radio, age unknown except the 6BA nutserts probably put it somewhere between '65 and '75

This achieves a wide tuning range of 2 - 10 MHz by coupling a variable inductor to a normal variable C, the inductance being varied by a shorted turn in the form of a copper sleeve which slides over the main winding. The tuning inductor is marked L11 and the long RFC is L12, the cap is C106

I can't imagine what this was out of, maybe a test oscillator, because it's most unlikely it was ganged to any tracking RF stages

[davidw]

Re #48 Searching the numbers makes it part of the transmitter section of an Australian Wireless station A510
https://www.qsl.net/vk2dym/manuals/A510_0546.pdf
page 14 of the manual which is page 20/63 of the pdf is a diagram which shows what looks like the same unit.

[Julesomega]

That's brilliant Dave! It is clearly closely related to the tx section of the A510, the differences being a) only a single range is marked on mine where the A510 PDF (page 22 plate C item 31) shows two scales on the dial, and b) the A510 seems to be motor tuned (page 24 plate E item 1) whereas mine has a tuning spindle projecting forward, with two O-ring seals to go through the case to take a knob

A VFO for a transmitter would not require ganging with other tuned circuits in a unit which relies on manual antenna tuning, as in the A510

[QQVO6/40]

Hello Julian and G'day to all.

Your item in post 48.
Dave is correct. It is the PA (power amplifier) tuning from an A-510 man pack radio.
You are correct in saying that it is not ganged to anything else. The master oscillator of the transmitter is crystal controlled so no need for complicated ganging.
The shaft does come out through the front casing of the transmitter and rotated by a control knob.
The dial with the two scales you mentioned is on the receiver and not the transmitter. The receiver is VFO (variable frequency oscillator) tuned and needed the dial spaced out a bit so it could be read hence the 2 scales.
No motors in an A-510.
Made by Amalgamated Wireless Australia in their Ashfield plant in Sydney.
Transmitter and receiver are in separate casings joined by a short cable. The radio looks just like a normal set of ammunition pouches and carried attached to a soldier's webbing in the same manner. If the whip antenna is not mounted on the radio the radio operator looks just the same as the other members of the section. ( Sorry for you people in the UK a squad). If a section is slack enough to walk into a well prepared ambush the first soldier to get knocked over is the radio operator so he can't call for backup. Hence the rationale to get the radio op to look like everyone else in the section.
The UK MOD thought at the time they were pretty good so bought quite a few of these sets so I guess that is how this sub chassis has ended up in your hands there Julian.
I have two A-510 radio sets complete and in working condition and have used them.
Do not bin the sub chassis you have as there will be someone that would love to make use of it for a restoration.

Cheers all.
Robert, VK2ZWZ.

[Julesomega]

Thanks so much for all the details Robert: after Dave identified the set I was hoping someone from Oz could add some detail. I must have picked up a couple of these at a rally sometime and I'd gladly pass them on for a restoration project, but first I'd like to use one to make a simple VFO for this useful frequency range

[Julesomega]

Just found something else for tuning something, but what could it be? Don't want to open it as it was sealed with Method II Preservation in 1958 and 1959 and packed in 1964 and says DO NOT OPEN until ready for use or inspection

What is a Tuner Radio Frequency Collins 504 9758 003?

I suppose I could inspect it...

[Buzby123]

Originally Posted by Julesomega

I suppose I could inspect it...

Only if you've got an 'RAF Form 4508 B' with this century's date on to re-seal it.

[Julesomega]

Why didn't I think to google for "Tuner Radio Frequency Collins 504 9758 003"? Probably cos I have better sense. Just tried it and there are dozens of hits to buy whatever it is, which now has a NATO stock number

[Julesomega]

I own up, it's been sitting on the stairs waiting for a destination for over a month so I opened it up. The amount of packing and desiccation is remarkable, including a thin sheet of soft aluminium which had been wrapped around the inner packaging. My excitement was not disappointed - can anyone explain what it could possibly be for? Of the 360° rotation, about 1/3rd varies the capacitance, and for the remainder the cap is shorted out by a long rod which forms a variable inductance at VHF, all in series with a ceramic trimmer

It's all a bit like the A-510 manpack variable cap + inductance discussed above

[Julesomega]

Something with a wide tuning range at VHF? Someone must have tripped over one of these at some point..?

Ok, maybe not - but what about this little test meter which is 3½ × 3 × 2", black crackle finish, and which, at 1½lbs, would make a sturdy paperweight. There seems to have been a label on the front between the meter and the zero adjustment, no doubt elegantly embossed in brass but without which not a clue as to the manufacturer. The nearest to an identity is the bit of sticky tape with some marks that suggest it might have been made in October 1979. The selector has a delightful action, rising no more than 10 thou' while rotated and clicking satisfyingly back into place with not hint of scraping contacts. The operation label on the rear calls for external shunts on the current ranges

[davidw]

#57 That looks like Post office telephones Dectector No4...see here http://www.vintage-radio.net/forum/s...d.php?t=71948e I've still got mine with its leather case and accessories.

[Radio Wrangler]

Some VHF sweepers had motor driven variable capacitors spinning away. These usually had ball races and were butterfly jobs to avoid needing grounding brushes.

David

[Julesomega]

Thanks Dave, a Detector No.4 indeed, and now I know what the missing label said! Anyone looking for one?

As David says, the Collins tuner was clearly for something that didn't get many full rotations, the switch fingers were not made for that