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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sat 14, 2019 5:50 pm 
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Location: Dallas, TX
Here is a picture of an ion trap for a mid 50's Admiral that goes to a set I have. The magnet is not very strong compared to many magnets you might run across today.
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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Sat 14, 2019 8:09 pm 
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Quote:
I think you also said you had gotten some publication on TVs, there might be more info there.


Thanks for the link and resources. I didn't know Television Simplified was scanned and available online. I actually bought the hard cover 6th edition of that book online as well as Basic Television Principles & Servicing 2nd Ed. by Grob several months ago after high recommendations.

Quote:
Here is a picture of an ion trap for a mid 50's Admiral that goes to a set I have.


These look quite similar to what I see around the deflection yokes (a metal clamp with a small box that seemed like a magnet on one side) but I assume one around a yoke couldn't be refactored for this. I haven't heard back from ETF but was able to find a matching one to what ETF indicated they had, which is an adjustable ion trap that can range from 32 to 55 guasses which should be perfect since the CRT schematic calls for a 40 gauss trap, assuming I know how to actually set it accordingly.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Wed 18, 2019 6:18 am 
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Since my last update, I purchased an 8xp4 test tube and some other items including a high voltage test lead. The anode reads in at a steady 15.5KV which is comfortably within the 14,000-16,000 range of the 21ATP4 and other CRTs.

The picture comes in nice and clear on the test tube but still exhibits the slow vertical scrolling issue and seemingly also the cut off portion of the bottom that has been present since I got the TV. I did spray F5 into the controls but that didn't have any notable improvement. The good news is that it still gets image and audio well so it does seem like nothing major is malfunctioning.

I have a couple more capacitors to replace and have still barely began checking resistors. I did buy a vintage TO-5 capacitor tester but have not experimented with that yet and will likely recap that as well before use.

I don't recall having the vertical sensitivity/scrolling issue the first time I got the TV back working again, so I may also try tracing back what caps I replaced back then to see if any of those are at fault.

I'll also be checking the pins of each vacuum tube especially the video-related ones against the specs and will share those findings this weekend.

In case the vertical transformer itself is bad I do have another available but I don't know enough to understand if that bottom cropped issue could be caused by that so first I will focus on the resistor and capacitor checks.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Wed 18, 2019 3:03 pm 
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Location: Pewaukee, WI
Can you get the vertical to roll slowly both directions adjusting the hold knob? If so then sync is not making it from the sync separator to the vertical, and you want to focus on the components in between the sync plate and the ocs grid.
If it only rolls one direction and the hold control is up against one of its stops the vertical osc is off frequency and you want to focus on the vertical osc.
Localization of problems saves time.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 1:09 am 
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Quote:
Can you get the vertical to roll slowly both directions adjusting the hold knob?


Yes. It can scroll slowly and smoothly in either direction by adjusting either the vertical hold or vertical linearity controls (both of them can make it go either direction). When I get the picture to the point where it is pretty well stationary, it feels like a slow drift takes affect where within several seconds it starts a gradual roll (mostly downward direction). I will check more into this over the weekend.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 2:02 am 
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Location: Dallas, TX
MattPilz wrote:

I have a couple more capacitors to replace and have still barely began checking resistors.

In case the vertical transformer itself is bad I do have another available but I don't know enough to understand if that bottom cropped issue could be caused by that so first I will focus on the resistor and capacitor checks.

Replacing the caps and checking the resistors might seem tedious but it is something that has to be done.
You may very well correct the problems you are seeing in the process. The vertical cutoff may be due to the vertical output tube being bias wrong due to a resistor being off, the signal is sitting too close to the edge of the operating range of the tube so the output can't go further.
Another resistor could effect the operation of the sync of the oscillator.
I don't thing that cutoff is due to the transformer, but if there is a lot of DC current through it, the core might "saturate" and not be able to output a complete signal swing.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 3:48 am 
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this is where a b@k tv analyst is invaluable. you would inject the correct signal at the grid of the vertical output tube and if you get a full pic you know the output tube and everything beyond that is good. if you stil dont get a full pic the output tube one of the components in the output tube circuit the vertical transformer or vertical winding in the yoke is at fault.

if the pic is good then inject your signal in the grid of the vertical multivibrator tube if gives you a full pic the problem is before that point. if not check the components in the multivibrator tube circuit.

i am sorry i havnt sent you the riders yet but i just found my disks today.

is the washed out poor contrast pic improved with the test tube? i suspect that is fixed and was caused by the weak crt.

voltage measurements in the virtical section should point to bad components also.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 7:22 am 
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Quote:
this is where a b@k tv analyst is invaluable.


Funny you should mention that, as I will have a B&K 1077B by this weekend! It's an untested unit but hopefully will be alright, I guess the main concern is whether the inside mini picture tube is still good or not for broadcasting the test image signals.

I also now own a Tektronix 475 oscilloscope, still untested by me but said to had worked.

And a smaller item I picked up was a flyback/yoke tester (EICO 944). I recapped that and tested with a compatible NOS yoke I got for my set and the tester seemed to work great. I haven't tried this tester with the flyback yet but still kind of convenient I guess.

The yoke required a fifth wire be added but was easy to figure out by the schematic compared to original. The new yoke is what I am using so that also rules out that as a potential issue point. Although the new one has a 56 (pf/mmf?) ceramic capacitor connecting the bottom horizontal coil leads while the original had none. (Schematic from original SAMs on left, NOS yoke on right). Any explanation for why some may have that capacitor and others don't?

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Quote:
is the washed out poor contrast pic improved with the test tube? i suspect that is fixed and was caused by the weak crt.


Yes, it definitely seems to be. I haven't given close analysis but I know the contrast is working well along with brightness on the new test tube. The text seemed sharp as well.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 3:21 pm 
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Joined: May Thu 14, 2015 4:15 pm
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Location: Dallas, TX
That scope should be very useful. Do you have probes for it?

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 5:05 pm 
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Joined: Sep Thu 20, 2018 8:53 pm
Posts: 109
Yes I ordered a few varieties that are compatible with it off of amazon. This set mostly, which seemed like a nice starter set:

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"Useable with oscilloscopes having bandwidth up to 200 MHz, Modular Construction ,Coaxial Design with Coaxial Reed Switch, Accessory Pack included ,1 Screw driver ,8 Marker bands ,4 Tip locating sleeves ,2 Mini Alligator Clips and Ground leads ,2 Interchangeable Probe Clip Tips"

"200MHz BandWidth,
x1/x10 Attenuation,
System Input Resistance: 10M / 1M, Tip/Head Style: 5 mm
Typical Input Capacity: 85-115pF / 18.5-22.5pF, Cable Length:1200 mm
Max. Voltage: x1: <200V DC + Peak AC, x10: <600V DC + Peak AC"

I ordered a few additional generic BNC probes as well with different ends including minigrabber but the 200MHz rated ones above would be the primary ones I'd use in oscilloscope.

Have a lot to learn about them but think it will be very beneficial for a lot of purposes including testing the points and reviewing the patterns compared to those in SAMs.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 6:52 pm 
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Joined: Jun Thu 25, 2015 3:21 am
Posts: 1352
your B&K 1077B should be new enough that it doesnt use paper caps. you may want to test the ecaps. if memory serves you said you bought a sprague teleohmike which would be good for that. for troubleshooting the B&K 1077B will be much more usefull than an oscope. the oscope is necessary for tv alignment work. do you have the different probes for the B&K 1077B?


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 7:42 pm 
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Joined: Sep Thu 20, 2018 8:53 pm
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No unfortunately the 1077B didn't come with any of the probes. I was hoping it'd use compatible probes like the ones I have, if not are they difficult to come by? I do have the manual for it but haven't read much yet.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 8:22 pm 
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not sure about the 1077b as i never saw one. i know my 1075 is an older version of the 1077b and it uses pin jacks for everything but the rf output and the rf uses an amphenol connector. this is a standart mic conector back in the day. i doubt i spelled amphenol right. i believe both are obsolete today. you could change the mic connector to bnc connector to use a more modern probe for the rf i suppose. there is a man on ebay who makes custom probes for old equiptment. when if you search my posts for a post about a hickok 209a someone provided me with a link to that gentleman's page to order old probes. you could contact him with what you need. when i have time i will look up the post on here and post the link on here.

i just found a picture of the 1077b and the amphenol connector is not used for the rf probe. it still uses pin jacks for everything else. i never used anything new enough to have a bnc connector on it as the test equiptment i use now and used in the past was from the 1950s or earlier hence im not sure what a bnc connector looks like. i will upload the pic of the 1077b if this site will let me. look at the connector below the rf attenuator.


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Last edited by thomas13202 on Sep Thu 19, 2019 8:33 pm, edited 1 time in total.
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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 8:26 pm 
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MattPilz wrote:
No unfortunately the 1077B didn't come with any of the probes. I was hoping it'd use compatible probes like the ones I have, if not are they difficult to come by? I do have the manual for it but haven't read much yet.

I just use a scope probe for the RF connection and home made wires with banana plugs on one end and alligator clips on the other ends.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 8:53 pm 
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one thing i forgot to mention is the 1077b needs to have transparencies with the different test patterns on them to work. i hope the unit comes with the test patterns.

Electronic Memory when you say you use a scope probe for the rf do you mean one with a bnc connector on the end? if so for my 1075 has a different connector and that wouldnt work.

the other jacks are pin jacks. i thought that bananna plugs were to thick to plug into a pin jack. since you say you do this it does work. good to know since the connectors for a pin jack are getting hard to find.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 9:11 pm 
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Joined: Sep Thu 20, 2018 8:53 pm
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The set I got comes with one transparency. However I do have a box of blank transparency paper and a monochrome laser printer so should be able to recreate many of them. Scans of the originals were posted to this link:

https://antiqueradio.org/BK1077BTelevisionAnalyst.htm

My set does come with the first slide shown which I believe to be the most important for checking distortion and such.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 10:07 pm 
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you are correct the circular pattern with the b&k on it is the one for black and white tv troubleshooting. there may be info online telling you how to interpret the different things on the pattern. the circle is used to set liniarity the lite and dark areas are used to set brightness and contrast if memory serves. the lines with the numbers next to them on the bottom tells the resolution of the picture and the lines on top with the numbers tell the bandwith. i havnt used one of these in 20 years or more. i am just starting to get the equiptment i need to get back into this.

the squares pattern and dot pattern are used for convergence of the color circuits in a color tv. although the pattern with the squares can also be used to check horizontal and vertical liniarity i prefer the circular pattern with the b&k on it. the indian head pattern is not a b&k pattern and must be a custom pattern the gentleman made on his own. in the old days some tv stations would broadcast a similar indian head pattern when they signed off the air at night along with a test tone.

the 1077b is basically a miniture tv transmitter and can be used to inject any signal into a tv set that it uses to locate problems in the set quickly and efficiently. start at the output of the section you are troubleshooting and work your way back one stage at a time.

it may be helpfull if you locate the user manual for the 1077b and read it.

here is a link to a great book explaining the proceedure for troubleshooting a tv with the tv analyst. it is referencing an older model but the procedure should be the same. controls may be located in a different place or may have a slightly different name.

http://oldtubes.net/library/free_manual ... lified.pdf

how you would use a computer and printer to make your own transparency i have no clue. hopefully you do.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 10:53 pm 
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thomas13202 wrote:
one thing i forgot to mention is the 1077b needs to have transparencies with the different test patterns on them to work. i hope the unit comes with the test patterns.

Electronic Memory when you say you use a scope probe for the rf do you mean one with a bnc connector on the end? if so for my 1075 has a different connector and that wouldnt work.

the other jacks are pin jacks. i thought that bananna plugs were to thick to plug into a pin jack. since you say you do this it does work. good to know since the connectors for a pin jack are getting hard to find.

I used to own a 1076 and it had those hard to get pin Jack's and amphenol connectors...I dumped my 1076 partly because I disliked it's jack pack.

The later 1077 used BNC and banana plugs which are incompatible with the older model B&K analyst connectors....you can't plug a banana plug into a pin jack... though you may be able to replace the pin Jack's with banana.

I kinda despise the old amphenol connectors and replace them with BNC wherever I don't have the factory cables...case in point my B&K 415 alignment generator is now all BNC.


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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Thu 19, 2019 11:47 pm 
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Location: Dallas, TX
Matt, one of the first things you should do before using the 1077B on the Admiral is hook it up to a working TV that can receive the old NTSC (analog) signal. That way you can be sure the B&K works. The cables for the 1077B send signals to the TV, the scope probes take signals from the TV. If the scope probes are used for the 1077B make sure they are set to 1X, not 10X. Personally I think if I had to choose between the two instruments to have I would go with a scope because it is more useful in general.

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 Post subject: Re: 1956 Admiral Console - Some general technical questions
PostPosted: Sep Fri 20, 2019 4:29 pm 
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The 2077B is definitely going to need some work. I tried turning it on last night and there is one resistor, I believe, that almost immediately lit up orange from overheating and billows of smoke came out. After unplugging, it could still be heard sizzling for some time.

It also has a lot of electrolytics in it, more than the admiral itself. I have the part list and schematic so will review it this evening and should be able to replace some of them over the weekend but others I dont have on hand. I can use it as a time to experiment with my capacitor tester too.

I realize the one tool still lacking from my arsenal is a vacuum tube checker. This becomes annoying especially when I get new tube based devices and have no way of checking the tubes at home. So I may start looking for one although they do get costly on ebay often especially one that tests more than just good or bad.


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