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 Post subject: Hickok 752 data: can anybody help?
PostPosted: Oct Sun 31, 2010 4:45 am 
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Joined: Jul Wed 29, 2009 8:39 pm
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Location: Kennesaw, Georgia
as I will be the proud owner of one come the 1st of November( MUCH better birthday gift that one's dog dying) I did some research and I ran into a problem: I can't find a data download or manual and bama has nothing... Does anyone have a PDF of these 2 things( manual and data/supplements) that I can use? Please?


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PostPosted: Oct Sun 31, 2010 6:27 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1050
Location: NW WA
Try this link. It's slow, but it does work, and the 752 data is there: http://web.archive.org/web/200602071748 ... erdata.htm

I sincerely hope this ends your search for tube testers and data forever.

-Steve W.


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PostPosted: Oct Sun 31, 2010 4:57 pm 
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Location: Kennesaw, Georgia
yes...I am done. I guess I got waaaayyyy too caught up in the "religions" of tube testers. I can only offer my apologies for my incessant posting here in regards to tube testers. I want to keep this brief as I feel some members have been rubbed raw by my folly, I know I have been rubbed raw by it.
my use of the word 'religions' was by no means an intended blasphemy.


:oops: :oops: :oops: :oops: :oops:


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PostPosted: Oct Sun 31, 2010 7:32 pm 
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I got pretty much the same way before my first tube tester purchase. And trust me, it's still not over yet. Once it arrives, you'll probably want to calibrate it. And the quest will once again begin. And if you got the shiny grey 752 manual with red lettering instead of the blue one, most of the specified calibration voltages are listed along with some of the calibration procedure. The remainder of the calibration procedure can be extrapolated from the military TV-7 repair and calibration manual.

The 752 is a nice machine. I like mine a lot.

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 Post subject:
PostPosted: Oct Sun 31, 2010 8:06 pm 
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Tubetechie105,

Don't be embarrassed or afraid to ask questions here. You know the old saying, "The only stupid question is the one that's not asked".

If someone thinks you are pestering them with questions then they can ignore you.

No one here knows it all (well maybe a couple - and they are usually willing to help).

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https://stevenjohnson.com - Steve's Antique Technology


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 Post subject:
PostPosted: Oct Sun 31, 2010 11:34 pm 
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Does anybody have the "shiny grey manual with the red lettering" so I could get a copy of the voltages and cal procedure?
Thanks

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Bruce


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 Post subject:
PostPosted: Nov Mon 01, 2010 1:27 am 
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Joined: Jul Wed 29, 2009 8:39 pm
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Location: Kennesaw, Georgia
maynardb wrote:
Does anybody have the "shiny grey manual with the red lettering" so I could get a copy of the voltages and cal procedure?
Thanks
Me and you both!! if I can get away with buying the manual I will send you a copy free of charge if you PM me.


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 Post subject:
PostPosted: Nov Mon 01, 2010 1:31 am 
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Here's some info that I found a while ago, I believe on this site.



"This is how I proceeded with mine. Maybe it's good, or maybe someone has a correction or something to add.

Calibrated the meter to .280 Ma FSD (it was at .278 - the meter shunt worked nicely).

Measured all my voltages with shunts where appropriate.

All levels were a little low by about the same margin.

Goosed the line adjust cal pot while watching the signal and heater volts to make a new cal point. So my volts came up.

Was lucky. The volts all fell into place. No moving resistor taps - thank you. Signal, B+, screen, heater, bias is all acceptable. Switched grid signal levels not too far off spec, which should be: SH=2.5vrms, X1=1.25vrms, X2=2.5vrms, X4=1.25vrms, X10=.50vrms, X20=.25vrms signal

And it's a good thing because if some voltages don't coincide you can't do that much about it anyway.

1meg leakage read right on the money.

I checked bias 100 and bias 22 but was not sure what spec to go by. The 533A calls for -43vdc and -3.3 vdc. The book spec for the 752A is 0 to -40 volts. total range. It seemed close enough to both specs, so I left it alone. Wonder what the right bias 100/22 values are. According to the German Tonewheel Tubeworks document it may be that it is -40/-3.12 vdc at settings 100/22.

There are two open-style pots, next to the line cal meter sense trim pot, that I did not need to touch and I don't know what they do. One must be leakage cal, other?

It seemed good. Works great. Not going to bother to check with signal injection. My standard tubes reading close enough. No big surprises.

1.25 vrms signal for a 12ax7, by the way.

Great layout. Very handsome machine. I think that the self-bias binding post may be a good place for an ammeter, but does not work on the 2nd half of twin triode - only good for section one. Got a dc reading on a 12ax7 of about 4.5 Ma on those jacks. And they seem to be reading a tad low in Gm at that point.

Sounds like this thing is probably done, right? Maybe Chris will be lucky with his and the levels will all line up on his 752A.

Or maybe someone will come up with the official method. Will be searching past post later.

Those Hickok people did know how to use transformers though.

View user's profile Send private message Send e-mail The 752/752A's secondary circuit should be calibrated at 1/2 scale.

Here are the AC RMS currents which should cause 1/2 scale deflection:

X1______ 0.94mA
X2______ 3.75mA
X4______ 3.75mA
X10_____ 3.75mA
X20_____ 3.75mA

X2 thru X20 ranges use the same secondary range by varying the input signal."


Good Luck and let me know if you find that manual info.

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Bruce


Last edited by maynardb on Nov Mon 01, 2010 1:55 am, edited 2 times in total.

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 Post subject:
PostPosted: Nov Mon 01, 2010 1:48 am 
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Joined: Jul Wed 29, 2009 8:39 pm
Posts: 665
Location: Kennesaw, Georgia
maynardb wrote:
Here's some info that I found a while ago, I believe on this site.



Hey Chris, hope your 752A goes good. This is how I proceeded with mine. Maybe it's good, or maybe someone has a correction or something to add.

Calibrated the meter to .280 Ma FSD (it was at .278 - the meter shunt worked nicely).

Measured all my voltages with shunts where appropriate.

All levels were a little low by about the same margin.

Goosed the line adjust cal pot while watching the signal and heater volts to make a new cal point. So my volts came up.

Was lucky. The volts all fell into place. No moving resistor taps - thank you. Signal, B+, screen, heater, bias is all acceptable. Switched grid signal levels not too far off spec, which should be: SH=2.5vrms, X1=1.25vrms, X2=2.5vrms, X4=1.25vrms, X10=.50vrms, X20=.25vrms signal

And it's a good thing because if some voltages don't coincide you can't do that much about it anyway.

1meg leakage read right on the money.

I checked bias 100 and bias 22 but was not sure what spec to go by. The 533A calls for -43vdc and -3.3 vdc. The book spec for the 752A is 0 to -40 volts. total range. It seemed close enough to both specs, so I left it alone. Wonder what the right bias 100/22 values are. According to the German Tonewheel Tubeworks document it may be that it is -40/-3.12 vdc at settings 100/22.

There are two open-style pots, next to the line cal meter sense trim pot, that I did not need to touch and I don't know what they do. One must be leakage cal, other?

It seemed good. Works great. Not going to bother to check with signal injection. My standard tubes reading close enough. No big surprises.

1.25 vrms signal for a 12ax7, by the way.

Great layout. Very handsome machine. I think that the self-bias binding post may be a good place for an ammeter, but does not work on the 2nd half of twin triode - only good for section one. Got a dc reading on a 12ax7 of about 4.5 Ma on those jacks. And they seem to be reading a tad low in Gm at that point.

Sounds like this thing is probably done, right? Maybe Chris will be lucky with his and the levels will all line up on his 752A.

Or maybe someone will come up with the official method. Will be searching past post later.

Those Hickok people did know how to use transformers though.

View user's profile Send private message Send e-mail The 752/752A's secondary circuit should be calibrated at 1/2 scale.

Here are the AC RMS currents which should cause 1/2 scale deflection:

X1______ 0.94mA
X2______ 3.75mA
X4______ 3.75mA
X10_____ 3.75mA
X20_____ 3.75mA

X2 thru X20 ranges use the same secondary range by varying the input signal.


Good Luck and let me know if you find that manual info.
who is Chris? anyway I asked about this to make sure but I just have the 752. I have yet to see a Hickok 752A go for less than $600+ and will I need a 6L6 calibration tube?


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 Post subject:
PostPosted: Nov Fri 05, 2010 9:30 pm 
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Joined: Nov Fri 05, 2010 6:45 pm
Posts: 4
TUBE DATA

Several posts here mention 752/A tube data available on the web; indeed there is. One common file is "752settings.pdf", which is found here: http://electotubes/752settings.pdf , at the Internet Archive site mentioned above by BPlus, and at some other places. This appears to be a roll chart scanned onto 8.5x11 sheets.

Unfortunately, this file is incomplete - there's no data for tubes between 6DJ8 and 6HS8 because the .pdf file is missing a whole page after the current page 7. (I discovered this because I need data for 6GE5 - a 12 pin compactron used in Heath SSB Single-Banders like HW-16, and for 6DQ6.)

I found two sites that sell 752 data; the cheapest seems to be http://www.vacuumtubes.com/manuals.html ; the other is RadiolaGuy. However, if these folks sell hard copy printouts derived from the 752settings.pdf file above, they too will be incomplete. I'm going to check with them about this.

752 CALIBRATION

Vacumtubes.com and RadiolaGuy also sell manuals with calibration procedures. While I haven't found any 752/A calibration information on the web, as noted above several sources mention that the 752/A circuits are very much like the TV-7 circuit, and the TV-7 calibration procedure can be used as a foundation. TV-7 manuals and data are available on the web for free, e.g., here:

http://www.militaryradio.com/manuals/TV ... es_Tester/

If anyone has 752A tester data (settings) for 6GE5 and 6DQ6, or the missing page from the data file above, or full calibration procedures for the 752A itself, I'd appreciate knowing about it.

Apologies if the info above is common knowledge - I just found this forum and joined it.

-- Les, W9XC


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 Post subject:
PostPosted: Nov Sat 06, 2010 12:27 am 
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Joined: Jul Wed 29, 2009 8:39 pm
Posts: 665
Location: Kennesaw, Georgia
W9XC wrote:
TUBE DATA

Several posts here mention 752/A tube data available on the web; indeed there is. One common file is "752settings.pdf", which is found here: http://electotubes/752settings.pdf , at the Internet Archive site mentioned above by BPlus, and at some other places. This appears to be a roll chart scanned onto 8.5x11 sheets.

Unfortunately, this file is incomplete - there's no data for tubes between 6DJ8 and 6HS8 because the .pdf file is missing a whole page after the current page 7. (I discovered this because I need data for 6GE5 - a 12 pin compactron used in Heath SSB Single-Banders like HW-16, and for 6DQ6.)

I found two sites that sell 752 data; the cheapest seems to be http://www.vacuumtubes.com/manuals.html ; the other is RadiolaGuy. However, if these folks sell hard copy printouts derived from the 752settings.pdf file above, they too will be incomplete. I'm going to check with them about this.

752 CALIBRATION

Vacumtubes.com and RadiolaGuy also sell manuals with calibration procedures. While I haven't found any 752/A calibration information on the web, as noted above several sources mention that the 752/A circuits are very much like the TV-7 circuit, and the TV-7 calibration procedure can be used as a foundation. TV-7 manuals and data are available on the web for free, e.g., here:

http://www.militaryradio.com/manuals/TV ... es_Tester/

If anyone has 752A tester data (settings) for 6GE5 and 6DQ6, or the missing page from the data file above, or full calibration procedures for the 752A itself, I'd appreciate knowing about it.

Apologies if the info above is common knowledge - I just found this forum and joined it.

-- Les, W9XC
Please please PLEASE alert me with what you find, I don't wanna blow $40+ only to find out that isn't all that data that could be had


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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Jun Sun 07, 2015 7:32 pm 
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Joined: Jun Sun 07, 2015 7:25 pm
Posts: 1
I have the test data pages you are missing. Tell me what the last tube in your list is and then where the next one starts. I'll copy these pages and attach them here.


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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Jun Sun 07, 2015 11:59 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 11993
Location: Mpls, Minnesota
The original post is 5 yrs old :roll:

Dave


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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Jun Mon 08, 2015 1:33 am 
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Joined: Nov Fri 05, 2010 6:45 pm
Posts: 4
May be 5 years old, but I'm still watching! :)

AZStuff, I've temporarily posted the whole pdf file here and you can see for yourself:

http://relentech.com/temp/Hickok-752-tu ... -pages.pdf

I did a cursory check of all the page boundaries, and here are what seems to be missing. The missing page(s) I see are between these tubes:

2HQ5 (last tube on 2nd page of the pdf file) to 2T4 (first tube on 3rd page of the pdf file)

6DJ8 (last tube shown on the 7th page) to 6HS8 (first tube shown on the 8th page of pdf).

13DE7 (last tube on 13th page) to 21LR8 (first tube on 14th page of pdf)

The end of the 14th page: 33GY7 data is corrupted by a bad scan.

6788 (last tube on 17th page) to 6814 (first tube on 18th page of pdf)

Thanks for any help - I will happily assist with rescans, inserting pages, etc as I can process .pdf easily.

- Les, W9XC


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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Jun Mon 08, 2015 4:17 pm 
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Joined: Apr Thu 11, 2013 11:03 pm
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Location: 649 Lacy Wilkerson Rd Roxboro, NC 27574
I also have a 752. I really like it. When you get a complete set of settings, please upload it to BAMA or somewhere (here?) so the rest of us can get it. I already had the file you have, plus an "obsolete" file, plus two different roll charts that came with my tester. Thanks.

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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Oct Sun 29, 2017 4:40 pm 
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Joined: Jul Wed 29, 2009 8:39 pm
Posts: 665
Location: Kennesaw, Georgia
IF, and thats a big IF, its still needed the test data for 6GE5 is this:
6GE5 6.3 1CB0-72A0 50 ___ X10 S5 300
6DQ6 6.3 7250-0480 36 ___ X10 __ 300 CAP=P HOLD DOWNS1 AND PRESS S5

If anyone has the data for 00A I would sure appreciate it but it may or may not exists.

If anyone knows whether the Hickok CA-4 will test more tube or the CA-5 will, based on data, I would be extremely grateful.
I am also desperately searching for the right adapter of these two. Gob bless you reading this!


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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Oct Sun 29, 2017 5:02 pm 
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Joined: Jun Fri 19, 2009 6:34 pm
Posts: 8068
Location: Long Island
The '00 and '00A are tricky tubes to test. If the plate voltage or current limits are exceeded even once, it is possible to damage them in such a way as to permanently reduce their sensitivity as detectors. There were some testers made in the 1920s which applied low voltages to protect against this, but unless you have something that is specifically made to test these tubes, I wouldn't try anybody's made-up settings or "borrow" settings from the 01A.

About the best you can do is check the filament with an ohmmeter. Emission can be checked with about six volts DC on the plate in series with a sensitive milliammeter or microammeter. Sensitivity as a detector is relative and can only be checked in-circuit.

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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Oct Sun 29, 2017 5:34 pm 
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Joined: Jul Wed 29, 2009 8:39 pm
Posts: 665
Location: Kennesaw, Georgia
Chris108 wrote:
The '00 and '00A are tricky tubes to test. If the plate voltage or current limits are exceeded even once, it is possible to damage them in such a way as to permanently reduce their sensitivity as detectors. There were some testers made in the 1920s which applied low voltages to protect against this, but unless you have something that is specifically made to test these tubes, I wouldn't try anybody's made-up settings or "borrow" settings from the 01A.

About the best you can do is check the filament with an ohmmeter. Emission can be checked with about six volts DC on the plate in series with a sensitive milliammeter or microammeter. Sensitivity as a detector is relative and can only be checked in-circuit.

thank you very very much! I wasn't aware of this. I guess I am still on the hunt to have the most complete tester, but I've mellowed out since my Original post.
I've just found a little info on the Rimlock adapter that was briefly made for it, and it looks like a home-brew adapter project now. If anyone needs European tube settings for the 752/752A let me know. Its dated to 1964 though, and I don't know if there was any later edition for euro tubes made.


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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Nov Wed 01, 2017 8:34 pm 
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Joined: Jul Wed 29, 2009 8:39 pm
Posts: 665
Location: Kennesaw, Georgia
I have found a suitable adapter( a Ca-5)! I wanted to ask here since I have had the tread up, but does any body have the Western Electric data for the 752? At one point Genoo had it but I haven't seen Hide nor hair of him in a while. I genuinely hope he is OK. I cannot thank you all enough. You have made my day with your help.


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 Post subject: Re: Hickok 752 data: can anybody help?
PostPosted: Nov Wed 01, 2017 8:56 pm 
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Location: Columbus Ohio
no need to find one tester that does it all. It's much more fun to have many testers.
Then, you will want a curve tracer.

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