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RCA logos and boxes

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RCA tube boxes changed style when their logo changed from the circle-RCA to large RCA letters.

The dates on box flaps show:

(9-60) date on box with circle-RCA as the logo (probably the date when this style of box was introduced)

(4-69) date on white and red box with RCA letters as the logo---this box still says made in USA.

(4-70) date on the all red box with RCA letters as the logo----this box says that the country of origin is on the tube.

My question is this: Did RCA continue to use up old circle-RCA boxes after they introduced (evidently in 1969) the RCA letters logo? It seems like they would since it would be difficult to time running out of the old style boxes.

I have some distributor stock (many 5-packs, mostly TV and FM tubes) and the old style boxes have the new style logo on the tube. Some of the tubes in circle-RCA boxes have date code DJ (May 1971). Anyone know for sure that RCA did this? Is there info on the web that I can’t find? Thanks, Mark
I can offer an educated guess, having worked for a large corporation with thousands of products that required re-labeling when their logo was changed:

1) Lots of raw inventory (pre-printed cardboard).

2) Lots of work in process and/or finished goods with the old logo.

3) The time it takes to update all the documentation and engineering prints.

4) The time it takes to replace all the tooling used to print the stuff itself.

Of course, the products with lower margins and/or lower volume get replaced the last.
Yes, that is what is probably the way it was, before "just-in-time" manufacturing.

I am not sure about the date codes on the boxes or anything else, except the letter codes for the dates on the tubes. I found concrete information about that.

I googled the subject and found forum histories with replies from those who actually worked in the industry back then.

There were also "service publications" about most everything. Some of them appear on the web from time to time, but nothing about box dates. Lots of pictures, but no dates.
Hi, yes, RCA did box tubes with the newer "letters only" logo in older style boxes, more info can be found in the book "Tube Lore" by Ludwell Sibley, well worth acquiring if one is a collector or just plain interested in tubes. Also contains a lot of useful short form info, especially for less common industrial tubes. I think Antique Electronic still have it for sale.

I went to work for RCA service company in 1966 as a TV tech when I finished active duty with the army. The following year during one of our weekly (or was it monthly) meetings it was announced that the old long standing "meatball" logo was to be replaced with something more modern and up to date looking.

We had a fleet of panel trucks that were slowly being replaced while I was there. I remember getting a nice new truck with the "modern" name logo painted on it. I also remember that not all things changed over quickly, but it took quite a while for the meatball to be totally phased out. It was not uncommon at that time to see both logos intermixed on parts, labels and boxes. Remember, RCA is/was a huge company with operations all around the country and lots of inventory.

OK, I just wanted to see about how far it was from 1966.

Every time I start going through these tubes I end up with more questions.

Servicmen kept old tubes, lots of them. An archived thread on another forum said that they exchenged them for new tubes. Not quite sure how that worked. The post was by a counterman at a distributor.

I'm looking for every clue that I can to find these not really new tubes.

There are five packs of apparently new tubes and every one of them is shot.

Some of it may have had to do with warranty/maintainence work. What I am trying to figure out is if there was an underground market for the year-old warranty pulls.
Yes, it was calibrated last week and had been in calibration since the last one two years ago.

It isn't the tube tester, it is the lot of tubes. The same tube number from another lot of tubes will test good.

This appears to be warranty service on certain circuits that worked for example half of a 6BN8 very hard. Another forum post by an ex-serviceman revealed that certain designs operated certain tubes near maximum and the failure rate was very high.

These were Houston facilities and may have been oil related............lots of money for service.

This last lot of tubes came from a guy who found them in a garbage can put there by the wife of a dead repairman. There was a considerable amount of distributor stock ( I recall finding a local reference in a box) that had fallen into the hands of a local TV repairman.

This is the third pile of this sort that I have run across....all of a sudden it happens. The warranty pulls seem to be from the distributor that sold it off as surplus.

Trying to figure it all out so I can know what is going on. It seems to happen once a year. The up-side, a 1953 RCA 12AX7 black plate, new, in the very bottom of the box with the most rat poop in it.
Motorola spun off Freescale almost 5 years ago. Some of the data sheets on Freescale's web site still have the Motorola name on them. There is no printing involved here, it just takes the ability to find something on a web site and fix it. If you have ever tried to find a specific item on the Freescale web site you will understand why it takes years to fix. I can remember getting semiconductors from Digikey in Freescale packaging with the "M" on the parts for almost a year after the change. Same goes for ON semiconductor. I can imagine that RCA went through an even longer changeover process since it was just a logo change. Tubes that were not volume sellers may have sat around for a while. I am sure that the business of changing date codes was not recently invented.

Its odd that so many are testing bad. Have you calibrated your tube tester?

I bought a lot of 200 Sylvania 6V6GT's (late wafer base stuff) that were still in the sealed bulk packs. Only 40 of them were actually useable. Many had lost their vacuum, some just tested bad, and some tested marginal but sounded terrible. Anything was possible near the end of the vacuum tube era.

The warranty pulls seem to be from the distributor that sold it off as surplus.

I heard of this back in the early 1970's (after it wasn't done any more). The returned tubes some how made their way into the truck of the guy who stocked the tube testers at the corner drug stores.

Another forum post by an ex-serviceman revealed that certain designs operated certain tubes near maximum and the failure rate was very high.

I was a Philco TV repairman in 1969 - 1970. We could go through a dozen 6LU8's in a month, all warantee.
I was hoping you would reply when I made the first post. I knew you had the background and the stock to know about it.

Yes, they couldn't just throw away everything that didn't say "ON' or "Freescale."

I have some tube testers from repairman businesses and they are emissions testers. One has "Nash TV" painted on the side. All of these bad tubes I find test like new for emissions. It is gm where they fall down. The emissions tester would tell them if it was dead or shorted and they used trial and error to find one that would work in a TV. This is probably one reason why the typical caddy has so many used tubes in it..........trial and error method.

The testers at the convenience stores, radio shack, etc were only emsisions. There were companies that sold seconds and used tubes in boxes with micro-writing on them. They checked fine for emissions.

What you said about the 6V6GTs rings a bell. I read a manuf. service sheet from the early 60s in the library that said the shelf life of a tube was only meant to be 3 years due to potential air leaks. I have wondered if the pin seals have anything to do with the situation. Possibly, they just made them and sold them in hopes that no one would check them for gm.

Some of these 5-packs all have the same date code so maybe they are just factory duds. I doubt that they all went bad together. I don't see this sort of thing with Euro tubes.

The Asian invasion began in 1964 and by 1968 the transistor had taken over in audio and radio. This is why there has been so much distributor stock laying around. There was a drastic reduction in quality control and then a massive market shift. Solid state TV took many more years.

I was told by a counterman in the late 1990s that in the late 1960s the manuf. dropped the quality control and went to an honor system where the repairman/customer just brought it back for an exchange. This opened the door to a situation where there was a market for visually acceptable tubes. He said he just took the tubes and the rep would swap for new ones.

I also recall someome saying that when he serviced mobile radios he would never use an RCA tube because they simply would not work. This hints of lack of quality control, poor gm.

There are transceiver websites that talk about how a Sylvania power tube is the only way to go. I was also told that the Zenith TO works much better with a Sylvania 1L6. This probably has to do with the factory tolerances for gm.

There are many former WE phone employees that post on forums. I found one last night that said the conversion to solid state switching system cut the failure rate drastically. These were WE tubes.

There is a very good website that tells about large lots of defective 5965 (computer rated 12AV7 with no quality control for noise or microphonics) tubes in an old mainframe computer. Some sort of inferior coating caused an emission that shorted the tube. This sort of thing could get expensive.

There was a large line-up of late color tubes like the 6LU8. Perhaps they were designed and applied in haste.

All-in-all it looks like tubes are difficult to make properly without a high defect rate. The employees sat all day and did something similar to sewing.

What is tragic now is that people evidently piled up crates of factory rejects for one reason or another and are now putting them into the market place. There was a market for them all along for reboxers like Standard Brand ("this tube may be used or a factory second") and other similar "suppliers.".

I bought some $1 ea 25L6GTs from AES in their tube sale a few years ago. Not a $5 tube for a dollar, a 25 cent tube for a dollar. They were branded SUMMIT and many were shorted and weak for gm. I have no doubt that these were factory rejects. Summit is still in business and has a website.

Motorola tubes are usually premium GE. They are some of the best tubes from what I have seem. Motorola and JAN military are almost always excellent.

One redeeming factor: I have found that many new tubes will come to life with 20-30 seconds of filament overvoltage. This is a B&K 707 that has enough of a power supply to put enough current through them to get them going. Hold the test button down for the last few seconds of the overvoltage and the hold it down until the gm starts to come up. It works about 25% of the time, on new tubes with both gm and emissions problems.

I read last night that when they flash the getter they use RF heating. It is conceivable that some of it gets on the grid.
hailteflon said:

All-in-all it looks like tubes are difficult to make properly without a high defect rate. The employees sat all day and did something similar to sewing.

I would add HIGH-precision sewing. Assembly tolerances were paramount. Proper fixture maintenance was all important. So were your cathode material's purity, the getter, maintenance of the vacuum equipment, etc. When tubes were king, it could be done.
However when the transistor onslaught came into full force, and tubes were seen by the companies as mature and nearing obsolescence, investment in the necessary tool and machinery upkeep dried up.
In addition, many of the old-timer engineers were starting to retire, and the newer engineers did not want to study something that was on its way out.

I worked for an ancient Sylvania factory in the late 70s and saw this happen firsthand. Some of the equipment we used was beyond decrepit.
The destiny of the human race has been greatly determined by what the current perception of “progress” is.

I found a download called “Transmitting Tubes for the Rangers.” A 1965 publication giving an account of the video equipment aboard the Ranger spacecraft that went to the moon before Apollo.

When people take pride in what they are doing they can accomplish miracles. The electronics of the 1950s and 1960s was quite primitive, but they made it work.

If you happen to have a decryption sheet for the 5-letter Sylvania date codes, please post it. Mark
Unfortunately, Mark, I can't help you.
When I arrived there, production of receibving tubes had already stopped. We continued to build CRTs (just another large tube) for close to 3 additional years. Sylvania was desperately looking for a buyer for the factory, and when nobody materialized, they shut it down for good.

Hitachi at first "appeared" to show interest in us, but all they did was to take whatever technical info they could find useful, then walked away from it.

Where did you find the download "Transmitting Tubes for the Rangers"? I googled it and could find no results.
I 100% agree on the miracles performed during the space race. People were really proud of whatever they were doing.
I clearly remember companies that made simple stuff -i.e. toggle switches- proudly advertising that they had been to space.
I haven't been able to find it. It was found by accident while googling another topic about tubes. The link was probably on someone's personal pages.

I looked through my search history, but not to be found, yet.

I will post later. It is in the history somewhere.

The JPL + ranger (Jet Propulsion Lab) will get you many results through google. I found many more NASA archives today, but not that one.

Back later.
Thanks a lot for the link...it is quite fascinating.

I feel that I was fortunate enough to be a child of the "space age". I remember very clearly the excitment, the amazement, the wonder at seeing the space achievments of both the US and the USSR.
Science at its finest.
That experience clearly defined my resolve to become an engineer. Which I later did.

We are going a little OT here...but it is good.
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