RCA AR88 Series Loudspeakers

[David Dunlop]

Thanks for the post. That pushes back the pocket watch holder mod a few hundred units earlier than we knew previously. Every little bit helps.

Cheers,

David

[Hermit6345]

In answer to your query as to whether the plate still exists on the bottom of my speaker David. It does indeed and as far as I can see, the DOM is 1944, the S/N is C-01075 the only other info being MI22201 and RCA Victor..I have the pocket watch holder and it just needs to be refitted to the three holes. Mine is still in daily use and was bought new in the 70s regards, Ian

[David Dunlop]

Fantastic, Ian!

That pushes the pocket watch mod back even earlier in 1944 and increases that particular production run by a few hundred more units.

Cheers,


David

[DangerMan]

Apologies for the delay, I have at last found my AR88 speaker.
It wasn't in the condition I remembered it, so a clean up was in order before taking photo's. Sadly the box is long gone.
Attached are underside view, rear view, and close up showing loudspeaker markings.
The orange RCA logo has flaked off the magnet but the other markings are still clear.
1 44 6 and 8 EM 6 are on the basket, with P2119 on the cone.
There is a small orange paint stamp on the outside right of the unit but this is undecipherable.

No holes anywhere, it looks identical to Mans Veldman's.

[David Dunlop]

Sorry to have been absent for so long again. Never a dull moment in life it seems. The AR88LF is still a dormant project, but some small progress with the speaker since I last updated.

I added a pair of spade connectors to the soder dipped ends of the speaker cable to make connection much more sensible to the rear terminals of the AR88LF.

Patiently monitoring eBay for the better part of a year finally paid off in that I was able to purchase a fully working, all black faced military pocket watch to put in the pocket watch holder I had found earlier. This watch even has original luminous paint that glows that delightful green in the dark. Just waiting now for the arrival of correct hardware to mount the holder to the front of the speaker.

I originally thought the factory hardware fitted to the three pocket watch holder screw holes was the correct bits (minus the finishing washers) but on closer inspection realized the screws were dome head slotted ones which would stick too far into the pocket watch holder if used, to allow the watch to fit properly. Then the lightbulb lit even more brightly when the 'finishing' washers finally made sense. RCA had added the holes for the pocket watch option to all speakers at some point, but not all end users of the speakers would want to use pocket watches, so RCA finished the holes with fancy hardware, which was only swapped out as required. Once removed from my speaker, I think I will place them in a small envelope with a note explaining their purpose and place them inside the speaker box for future reference.

I will post a picture when everything is finally together on the speaker.


David

[shortwaverx]

This is mine, complete with the three holes. Sorry about the odd angle of the speaker photo.

[David Dunlop]

Thanks, Ian. Every little bit helps.


David

[David Dunlop]

Well I had a fun morning today working on my AR88 Series Loudspeaker. I really do hate taking things apart that are functioning perfectly well, but in this case, I needed to open up the loudspeaker case to access the finishing hardware in the front to remove it, as well as install the bakelite pocket watch holder I had purchased a while ago, where the finishing hardware was located.

Some interesting surprises in the process.

This first photo is of the eight factory screws RCA used to install the rear cover plate to the speaker case. I had not noticed it earlier, but as you can see, the four corner screws are more robust than the for inner screws. All the same thread, but the inner ones are shorter and of a domed or mushroom slot head style. The corner screws are flat slotted pan heads with a longer shaft. That struck me odd at first until I remembered in the early production of these speakers, RCA had provided small, formed sheet metal hangers on the four corners, so these speakers could be wall mounted if required. I am assuming that when the hangers were discontinued, RCA just kept production rolling with the existing screws.

David

[David Dunlop]

The next surprise came when I removed the rear cover plate. The lighting wasn't good in the corner of the shop I was working in and I first thought someone had done a horrible job of painting the inside of the cover.

When I moved to better light, I realized what I had been looking at was a band of thick paint applied one quarter inch inside the outer edge of the cover, into which had been pressed a patch of fine black speaker cloth (approx 100 thread count to the inch).

On closer inspection, it turns out to be the same cloth that is installed behind the circular, perforated grill on the front of the speaker.


David

[David Dunlop]

The third surprise was inside the case when I looked at the back of the speaker element. Knowing this speaker had been manufactured in Montreal, Canada by RCA, and with yellow C-Broad Arrow stamp on the bottom of the case, I expected the speaker element inside would be of Canadian, or possibly American make. The idea of keeping the supply lines simple, was stuck in my head. This does not seem to be the case.

The only two markings to be seen on the speaker element are a black circle with R.C.A. inside at the top and a black Broad Arrow inside at the bottom. Below this stamp is a large red Capital P, with a Broad Arrow stuck to the foot of the P and a red arrow barb at the top left corner of the P.

The black stamp would suggest this item came from the UK. I have seen the red stamp somewhere else at one time, but cannot recall it's origin.

David

[David Dunlop]

Once I had removed the finishing hardware from the front of the speaker case, I took this picture of it and then put all three sets of hardware in a small zip lock bag with a note of explanation and placed them inside the case when I closed it all back up.

This hardware is basically 4BA x 3/4 " countersunk screws (oddly with Phillips heads) and corresponding finishing washers, flat washers, lock washers and hex nuts as per this photo.

The hardware needed to install the bakelite pocket watch holder is a 4BA x 3/8 " countersunk screw with a slotted head, and corresponding hex nut.

David

[David Dunlop]

Last photo for the day shows the completed speaker assembly now sitting atop it's AR88LF Receiver. The black faced GPTP pocket watch was recently found. It is a perfect worker with complete, original wartime luminous paint.

Now that the speaker has been completed and a set of RCA headphones found, I cannot put if off any longer. Time to start digging into the AR88LF itself to document what needs fixing, replacing, finding or is in GWO. I can feel my muscles cramping up already.

David

[G6Tanuki]

Originally Posted by David Dunlop

Once I had removed the finishing hardware from the front of the speaker case, I took this picture of it and then put all three sets of hardware in a small zip lock bag with a note of explanation and placed them inside the case when I closed it all back up.

Doesn't this rattle at high audio-levels??

[David Dunlop]

Good question about the potential to rattle. I wondered about it myself, and not wanting to reopen the loudspeaker case down the road again if it did rattle, I reassembled each hardware set onto it's original screw and wrapped them in a small patch of cotton cloth before stuffing them in the zip lock bag and popping it into the case. Should be quiet as a church mouse now.

David

[M0TGX Terry]

Is it a good idea to have a mechanical watch mounted close to the permanent magnet of a loudspeaker? I was under the impression that watches were prone to being adversely affected by magnetism, and should be kept well away from magnets.
Apart from that, I am impressed by the speaker restoration. My own AR88LF will probably have to make do with whatever speaker I can find. Not a problem at present as I haven't yet summoned up the strength to start work on the radio! Not even sure I have the skill to sort it out even if I could manage to lift it.
Terry

[David Dunlop]

Just noticed another RCA AR88 Series Speaker for sale on eBay today. Data plate on it shows 1944 production with serial number C-01280 and no pocket watch holder set up on the front. Standard back cover with two vertical vent rows.

David

[David Dunlop]

It's been just over a year now and my AR88LF seems to be running well, so I am still putting off pulling it out of the cabinet for a look see/cleanup. In the meantime, however, I have put three or four hours on the clock with it connected to it's speaker, so thought I would update a couple of points raised earlier.

First, there has been no noise generated by the hardware I stored inside the speaker box. Been quiet as a church mouse.

Secondly, the pocket watch has been sitting full time in it's holder on the front of the speaker. Each time I use the receiver, I wind the watch and reset the time. It has been running perfectly with no signs at all of it not tolerating being in such close proximity to the PM on the speaker. This is probably far more time accumulated than any pocket watch would have received during wartime. From a few conversations I have had with Signals Veterans, these pocket watches would grow legs very quickly if left unattended and the rule of thumb seems to have been each operator took his or her watch with them when off shift.

David

[David Dunlop]

There is one more of these speakers popped up on eBay in England. From what I can make out of the photos posted, it has a none original speaker lead but is otherwise in very good shape. Canadian made in Montreal, with SN C-01631 and a production year of 1944. It is also equipped with the factory holes on the front for the pocket watch holder. Nice to add it's information to the list here.

I think it is in Hereford. The eBay item number is 322218701970.

Funny how things like this show up in waves. Lots one minute and nothing at all the next.

David