Been up at my camp for the past several days. New central air is being installed tomorrow. While being up here, I learned of a guy nearby in this neck of the woods with an old console tv. At first, I didn't give it too much thought. Went to go have a look, and found it to be a typical looking b&w 21" 1950's Philco. On the front, it's listed as a "Diamond D" which is something I've never really heard of before. Model number is UE4605T. Sams website says it's in 374-9.

After pulling the back off, I found a decent looking chassis with a little dust... not too bad. One pleasant surprise was finding that the CRT had been replaced and the warranty card was still in there from October 30, 1965. That's a big plus. Although I couldn't check it, I'm going on the notion that it's still good. The tube diagram inside lists the original tube as a 21BSP4. The new RCA tube installed is a 21AMP4. The current tube is aluminized. I'm guessing that the original tube was not.

Also, I found this set has motorized power tuning, and apparently had a wired remote. Unfortunately, the remote was no where around. There are two buttons on the top of the set... one for on/off, and the other is for power tuning. So, if it turns out tuner motor still works, I can use the button to change channels.

Looks like it's been serviced quite often. In addition to the crt, most of the tubes have been changed with various brands. I was only able to find two Philco tubes in the set that looked like originals. They had 1956 date codes on them. Also looks like a few caps on the boards have been changed.

The guy was asking 50 bucks for it, and while I normally wouldn't give that much for a typical b&w console, I decided it might be worth it considering the CRT had been replaced and it had power tuning. The guy even loaded it in his truck and brought it to the cabin for me. He was glad to get it out of his way without having to throw it away.

He told me the set was at his grandparent's lake house and he was under the assumption that either they found it at a garage sale or it was given to them... he thinks during the 70's. I showed him the warranty card for the toob. It had a local Beaumont address, but did not recognize the name. He's not even sure if they ever used the set.

Overall, the set looks pretty good. The cabinet is the fake wood stuff and needs a good cleaning. There are some light scratches on the top, but nothing too serious. The knobs and trim are not as shiny as they once were, but the set is quite presentable as is.

Since I am at camp, I don't have any instruments to test anything with. Although the chassis looks pretty decent, I'm not going to try powering it up till I get my variac from home. I might consider pulling the 5U4 out to kill B+ and try turning it on to see if the power tuning will function.

That is an awsome grab! Normall I am not too fond of grabbing pre 60s b&w sets, but that looks to be in great shape. Shame that you don't have th remote, but someone in the world may have one. There's always e-spray and cragislist.

Big congrats on that philco. It would be awsome to see pictures of your clean-up and referb process. Good job!

I've got a spare chassis with power tuning; as I recall it was pretty easy to make up a remote since it just has a few wires to hook switches to. But yours might be more deluxe-though they are about the same age mine has a horizontal chassis. This is probably the model that replaced what I have. I know I have seen ads for the Diamond D, in old Life magazines or some such.

as I recall it was pretty easy to make up a remote since it just has a few wires to hook switches to.

Hey, your right! Making a remote would be a breeze! Thanks for that idea! :thmbsp:

I guess I am going to need to get some extra "basic" tools and instruments to keep here at the cabin... because I have been itchin to play with this set all day. Hell... i don't even have a volt/ohm meter here. :no:

I pulled tubes to clean off the dust and was checking out date codes. Apparently, this set was last serviced by someone during the 80's. The damper tube was branded an Admiral with a date code of 1983 on it. All of the others were dated in the 50s and 60s.

I left out the 5U4 and plugged in the power to see if the power tuning still worked. Pressed the button on top and the tuner went thru the channels just fine... stopping at the ones it was set for. That's cool! Hope i have that luck with the rest of it.

Although the guy that had the set has no idea whether or not the remote was around when his grandparents had the set, he told me he'd keep an eye open for it. He said there were several boxes of stuff from their lake house and it was possible it could be in one of them.

Nice find on the Philco Diamond D. That TV came out during my tenure at Philco and I rate it among the three best Philco B & W chassis. The originals did have aluminized picture tubes. That TV will show a great picture if it's working right.

Tighten the 1/4 " hex screws on the PC boards as a preventive measure. They hold the PC board to the chassis to complete the circuit ground. Goofy intermittent problems show up if they're loose. Sound detector transformers could also be troublesome. Otherwise only routine maintenance is expected. You will be very pleased with the performance.

Good luck,

Don

I couldn't stand it anymore, so, last night I decided to drive home (about an hour drive) and get some gear to bring back to the cabin so I could play with this set.

This morning, I started out with the CRT which tested fine. After that, I looked around a little closer to see if any parts looked near death. Everything looked okay, so I pulled the HO tube and decided to do a very slow soft start. After a few hours of inching the juice up, everything seemed okay. The lytic cans were a little warm, but not so much to cause concern. The B+ voltages were pretty close to spec. Looking promising at this point.

TV is extremely hard to pick up in these woods, so, I connected a dvd player and was able to get some audio. It was somewhat weak, so I went thru checking and replacing tubes along the path. No changes. I have all the tubes except one... the tuner's RF amp. The tube chart showed it as a weird number like X-155. When I jerked the tube out that was in there, it was labeled 6BS8. I'm sure i'll find that later.

After letting it run for a while like this, I decided to plug in the HO tube and see if I got any kind of light on the screen. I did get light, but only a white line going across. Tried changing both the verticle tubes, but no change. Guess I'll know where to start when I pull the chassis out for changing caps.

At least I have something to work with here... a signal and light on the screen is promising. I'm sure once I get all those black beauties out, things will start to shape up. I'll probably pull the chassis after dinner.

Stay tuned.

Good luck & BE CAREFUL, Charlie...-Sandy G.

The signs are good.

Keep the brightness set very low until the white line is corrected. That indicates vertical problems. Usually nothing serious. Try adjusting the vertical lin and height controls first. To find them, remove the front plastic knob cover assembley. You will note that the control shafts are hollow and the knobs have small holes in the center. The height control is down the center of the vertical hold control and the lin is down the center of the brightness control. You will need a very thin screwdriver.

There are two tubes in the vertical; a 12AU7 on the PC panel behind the controls and a 6CM6 on the chassis. There are two 12AU7s on the PC panel. Vertical is the lower one.

Tighten the hex screws that hold the circuit board in place.

The X-155 is no big deal. 6BS8, 6BZ8, 6BZ7 will all work fine. There is a 1,000 ohm 1/2 watt resistor in the tuner that has a high failure rate. If you have snowy pictures after everything else is working, and you have replaced the RF amp, look for the 1K. It is likely burned. Also make sure the range switch is in the center position. That's the little flag switch at the bottom of the control cluster.

You're well on the way.

Don

Anyone know what the "Diamond D" means?

veg

Anyone know what the "Diamond D" means?

veg

Marketing hype I think, bout the same as "Golden Grid" :D

You can use a .047 600 volt cap hooked to the ungrounded side of the 6.3 volt filament circuit to help troubleshoot the vertical circuit...hook the cap output up to the grid of the vert output stage and the feedback stage and you can see if there is any amplification through the stages or where the circuit is broken.

True, Diamond D was a marketing differentiation. Philco had two new console lines in '57, Golden D and Diamond D. The Diamond D was the high tier line. Transitone was revived for first year portables.

Don

Yeah, but "D"? I could see Diamond P, but that D just seems odd.

veg

Yes, Veg, I see your point... "P" for Philco. Would make better sense.

I am currently changing out caps... lots of Black Beauties in there. Found one with a big crack under the deflection sub-chassis.

I can see why they would consider this to be the top of the line series. Chassis seems well built compared to many other b&w chassis of the time. Definately a lot easier to work on than my Predicta! :yes:

Hey Charlie,

Take a look at #5808414330. It might be the one?

Thanks for pointing that remote out. I do not think this is the correct one for my set, though. From what I can tell looking at the chassis and schematic, the remote only operates the power on/off and power tuning. The one on ebay also does picture brightness and volume.

I was noticing that the cable for that remote sure looks thin considering there must be at least 8 wires in there!

I am a little surprised that Sams doesn't include a remote page in the TV schematic for this set. There's also no reference to finding it in another folder.

[QUOTE=Don Lindsly]True, Diamond D was a marketing differentiation. Philco had two new console lines in '57, Golden D and Diamond D. The Diamond D was the high tier line. Transitone was revived for first year portables.

Charlie,

Check out this 1956 Philco "Diamond D" ad:

http://cgi.ebay.com/56-Philco-Diamond-D-TV-Miss-America-Marian-McKnight-Ad_W0QQitemZ6209197963QQcategoryZ3638QQssPageNameZ WDVWQQrdZ1QQcmdZViewItem

-Steve D.

Steve,

Yes, I saw that earlier today. I think that's the first time I've seen one of those ads. Usually, I see the Predicta "Miss America" ads. The set in the center bottom of the ad looks similar to the photo on the front of the photofact. Too bad my set isn't on there.

Currently, I'm changing the last of the lytics. Someone had already changed the caps on the deflection board. I just left those and changed the rest. There were a couple of BB's that were off spec quite a bit... and another that had a big crack. Had all radial lead BB's on printed circuit. Have to leave one of the BB's on the audio board... a .47 @ 200... don't have one here with me. I can always change that one later.

So far, I've made good progress with the Diamond D. Things have improved dramatically, but still have a couple of buggers to look for.

One of the initial problems in the set was no vertical deflection... it just had the typical white line going across the screen. The vertical opens up now, but, not near enough. The raster is crunched up only covering maybe half the screen. Tried adjusting the height controls, which had an affect, but not enough affect to correct the problem. In the past, someone had changed about 4 or 5 capacitors on the verticle/horizontal board, so I left them in place. Not changing them was probably a dumb-ass thing to do, so I will start there. I'll also go back and double check my previous work, as it's always possible i could have made a mistake installing a cap with the wrong value.

Also, I seem to have a signal strength issue. The signal I am now getting is far better than before I started, but, I still felt it was just a little bit weak. If I let the set run for a while... say 30-45 minutes, all of a sudden the signal comes in 100% improving both sight and sound. It stays that was a few seconds, then goes back to the weaker state. It continues to do this but each stronger cycle last a little longer than the previous one. Tried tapping around on components and jiggling tubes back and forth, but didn't find anything that way. While the chassis was out, I tightened up the screws on the boards pretty good as Don pointed out they are ground connections. Perhaps I will also try dabbing a little solder on them as well. The problem obviously gets better as runs, so, something in there is changing with temperature. I did not change the 1000 ohm resistor in the tuner that was mentioned earlier since the resistance measurements at the tuner's tube sockets were within spec. I might go back and change that resistor anyway just for the hell of it.

That's about it. Once I get those two bugs worked out, this set should play very well. Even now as it is, it makes a really good picture (although crunched up). Has good brightness and contrast.

A couple of quick checks. Measure the tuner AGC. It should be about 2 volts negative. If it's much more, it's an AGC problem. There is 12 meg resistor from B+ to tuner AGC to bleed down the tuner AGC voltage. If it is an IRC it probably should be changed.

Also remove the 6AV6 audio amp tube. It is also the AGC clamper. If the weak signal recovers, the tube has heater-cathode leakage and is rectifying the 6 volts AC.

Also I would make sure the 1K RF plate resistor is good. It goes from plate circuit to B+. The B+ is a high resistance to ground and a defective load resistor may not show up in a resistance check to ground.

Don

Things have come together on the Philco! Found the weak signal was caused by two 470K resistors in the tuner. One of them was open, and the other was reading nearly a meg. Signal is good and strong now.

Changed all the caps on the verticle/horz board. Previously, I had left those because they had already been changed before. Raster has now opened up covering the entire screen with a great picture.

Noticed that the vertical hold seems touchy. Gotta work with it to get a lock, and after the set runs for about an hour, it drifts and starts rolling. Great... just when I thought I was finished! I'm a little surprised it's having this issue being that so much has been changed in the sync and oscillator section. Swapping tubes with new ones had no affect. Oh well... I'll find it later.

I starting to think that perhaps Philco should have come up with another name for this series other than Diamond D. This set had many problems to be corrected. It also looks like it's had several service calls in the past considering the number of tubes that had been changed (all but one). It's had several caps changed in the past, and also the CRT. In addition, Don has pointed out a few failures to look for that was common for this series. With all this being said, maybe Philco should have considered naming it the Philco Cubic Zirconia D! :scratch2: :D :yes: :lmao:

The shots of the Mamas & Papas came off a DVD I recently found that talks about their history and shows great performances they did on shows like Ed Sullivan and Shindig. Watching on a color roundie is great! Lots of 60's colors on their clothes and the stage. I've loved their tunes since i was a kid. They were one of my mom's favorite groups, and the exposure I had to their music grew on me at a very young age.

After being aggrivated by vertical drift last night, I decided to monitor the B+ for a while. Specs call for it to be about 275 volts. I found it slowly go up and down... mainly down. At one point, it was riding around 235 volts. The highest it would go was 270. I've plugged in a new 5U4 and now the B+ seems more stable. A little low at 262 volts, but at least it's not drifting all over the place. I'll run it this way for a while and see how it works. I did have a little bit of drift on the vertical earlier, but it wasn't enough that I couldn't adjust to correct it. I'll tear it apart again later to see if there is somthing I've overlooked. It's possible I could also have a resistor that's drifting in value as the chassis heats up.

More pics...

Abner! Look what's going on at the Stevens's!

Nice job, Charles!

veg

Last night, I changed out all the resistors surrounding the vertical osc and sync amp. The old ones I pulled out all checked within spec, but, apparently one or more of them was drifting in value as the set ran. Now, the drifting vertical roll has been corrected and getting a lock is easy! Yay! :banana: Watched it last night for about 3 hours without ever needing to touch the vertical control. :smoke:

Interlace is a little bit out of whack, but not so much that the lines have completely merged. I was going to build a new vertical integrator, but am short a couple of capacitors. I'll build one later when I get home. I should have everything I need there.

In my last post, I mentioned having unstable B+ voltages. When I changed the 5U4, the B+ became stable at 262 volts. Apparently, the failing resistors in the vertical/sync sections were a strain on the B+ because now the B+ is stable at 278 volts (specs called for 275). Cool! Killed two birds with one stone! :D

There is one last issue that I've discovered... high voltage at the crt calls for 16KV. I am getting nearly 21KV. How can I tune this down??? There is no HV adjustment. :scratch2:

The picture this set makes is quite impressive. I've been using the DVD player on it. Late last night, I tried tuning in stations only using the set's internal antenna. Picking up stations up here in the woods is usually difficult, but I was able to get a few. Surprisingly, the station that tuned in the best was channel 11 out of Houston.

Charlie:

I would reduce the width to about 1/2 to 3/4 inch overscan on the sides. Make sure the 6500 ohm, 7 watt 6DQ6 screen resistor is not shorted. Other than that I would not attempt to reduce the high voltage.

Measuring high voltage did not come into fashion until it was mandatory for color TV so service personnel rarely knew what it was or were concerned with it.

Anything creative you do to lower the high voltage will either reduce width or load the flyback. Both should be avoided.

Don

Don,

The width did the trick. Thanks. I had adjusted the width a couple of days ago. I guess once I got the B+ up to 278 volts last night, it increased the width beyond where it was supposed to be and I didnt think to go back and check it again last night. HV is now running at 16.5 KV.