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 Post subject: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Wed 11, 2017 7:52 pm 
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Joined: Sep Wed 30, 2009 4:15 am
Posts: 7
Location: redwood city, calif 94061
does anyone know the real difference between the two? going to augment either with a 667 checker but trying to see which of the 2 military checkers out weigh the other and why,
cheers and 73sw to you all

PS will be firing up my 40mtr (160-40) WS-19 Canadian soon, on a wire antenna, sure would like to know if any of you folks want to try for a contact in a month or so.ciao


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Wed 11, 2017 8:42 pm 
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Joined: Feb Thu 13, 2014 4:57 pm
Posts: 19
Location: Burnaby, BC, Canada
The main difference between I-177 and the TV7 is that the latter doesn't have any 9 Pin (or above) sockets, so you must get a hard-to-find adapter to test newer tubes like the 12AX7.


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Wed 11, 2017 11:15 pm 
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Joined: Sep Wed 30, 2009 4:15 am
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Location: redwood city, calif 94061
wow thank you i have been offered a i-177 and the mx-949 adapter for 150 think ill jump on it


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Thu 12, 2017 12:15 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 953
Location: Tucson AZ
I'd jump FAST on that deal!


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Thu 12, 2017 1:15 am 
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Joined: Jan Thu 01, 1970 1:00 am
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Location: Latham NY
One of the main differences is the grid drive signal. The 177 only has a fixed 5 volt signal, the TV-7 has a 5v as well as 1v and .5 v settings. This is important in testing the newer 7 and 9 pin tubes.


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Thu 12, 2017 4:04 pm 
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Joined: Jan Mon 28, 2013 9:35 pm
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Location: Santa Rosa, CA
I've had and used both (I-177, MX-949 and TV-7's).
The TV-7 is better built and will test more tubes.
Steve


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sun 15, 2017 1:27 am 
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Location: Latham NY
Having owned and repaired and calibrated both I can't agree that the build quality on the 177 is not as good as a TV-7. Different companies were contracted to build units to the gov't specs, my 177/B was built by Simpson, been using it for about 30 yrs. I have a TV/2B/U that was built by the JH Keeney Co. whoever that was but is top quality.


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sun 15, 2017 10:25 pm 
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Location: Lincoln City, OR
Greetings to the Forum:

pelud writes:

Quote:
The main difference between I-177 and the TV7 is that the latter doesn't have any 9 Pin (or above) sockets, so you must get a hard-to-find adapter to test newer tubes like the 12AX7.


Is it possible that you have this backwards (meant "former" rather than "latter")? My TV-7 B/U has sockets for both 7 and 9 pin miniature tubes.

Regards,

_________________
Jim T.
KB6GM


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Thu 19, 2017 8:58 am 
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Joined: Feb Thu 13, 2014 4:57 pm
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Location: Burnaby, BC, Canada
Yes, you are completely right. I meant to say former.

I guess as the saying goes, I'm not lysdexic and I believe in dog.

Jthorusen wrote:
Greetings to the Forum:

pelud writes:

Quote:
The main difference between I-177 and the TV7 is that the latter doesn't have any 9 Pin (or above) sockets, so you must get a hard-to-find adapter to test newer tubes like the 12AX7.


Is it possible that you have this backwards (meant "former" rather than "latter")? My TV-7 B/U has sockets for both 7 and 9 pin miniature tubes.

Regards,


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sat 21, 2017 1:52 am 
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Joined: Jan Mon 18, 2010 2:13 am
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Location: Dayton Ohio
As mentioned, the I-177 is great for preWWII big tubes (octal and older) but are very hard on newer miniature, pushing them past their limits.

-Steve

_________________
Radio Interests
-Zenith
-Sparton
-Pre-War FM
Consoles and floor models, the bigger, the better!


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sat 21, 2017 5:26 am 
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You'll need the (rare and quite expensive) MX-949 extension/adapter to test miniature noval (B9A) tubes and the patching/unpatching method needed is slow, tedious and error prone. For exemple, checking both sections of a 12A*7 series dual triode is a long process and what only takes a couple of seconds on a TV-7 needs a few minutes on the I-177/MX-949 combo. I had these and quickly sold them without regrets. One of the most inconvenient tube tester I ever had. There are many more user-friendly and accurate tube testers available than the I-177. Only good for antique radio tubes and if you can get it really cheap (40 to 60$ without the adaptor).


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sat 21, 2017 6:51 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 953
Location: Tucson AZ
The mx-949 isn't that rare, but they can be pricey. Not too difficult to make one for yourself if you wanted too. I did.

I've never found using the MX-949 so slow and tedious. Yeah, it might take a little longer to test some tubes, but when was the last time the end of the world hinged on the speed of how fast a tube was tested?

If you can find a decent shape I-177 for 40-60, then buy it for sure because that auction site shows market value of the 177 to be higher than that, contrary to anyone with the opinion of 40-60.


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sat 21, 2017 7:14 pm 
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Joined: Jan Mon 18, 2010 2:13 am
Posts: 13389
Location: Dayton Ohio
I found this Espey model 105 which from what I can figure out is the same as an I-177.

Definitely a keeper!

-Steve


Attachments:
espey105.jpg
espey105.jpg [ 88.81 KiB | Viewed 35 times ]

_________________
Radio Interests
-Zenith
-Sparton
-Pre-War FM
Consoles and floor models, the bigger, the better!
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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sat 21, 2017 7:18 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 953
Location: Tucson AZ
That's freakin neat!


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 Post subject: Re: I-177 compared to a TV-7b,d,/u plus
PostPosted: Jan Sat 21, 2017 9:30 pm 
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Joined: Jan Thu 01, 1970 1:00 am
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Location: Latham NY
Sure looks like it's the same, never seen one of these.


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