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DaveC <not@home.cow>: Jun 01 08:38PM -0700 http://imgur.com/yIx0dC6   Original on the left, purchased replacement on the right.   Questioning whether these are equivalent for an old General Electric motor starter overload (CR106).   Seems like slightly different approaches to get a bimetalic bend effect when a specified current flows through each of these. One requires a resistance wire to heat the metal, whereas the newer one incorporates the resistance in the metal? Is that what's happening?   Does the element do the physical "tripping" of the OL, or do these do nothing more than generate heat which heats up the separate mechanism that opens N.C. contacts?   Thanks.

Ralph Mowery <rmowery28146@earthlink.net>: Jun 02 12:08AM -0400 In article <0001HW.1CFFE1A000174A8F114D213CF@news.eternal- september.org>, not@home.cow says... > nothing more than generate heat which heats up the separate mechanism that > opens N.C. contacts?   > Thanks.   All they do is generate heat. The part that is heated is in the block those things go in. That is where the actuall tripping goes on. It trips a small switch and if you look at the block they go in you will see the screw terminals for the actual switch. If you could turn them so they are outside the block, nothing would actually be heated and the switch would never trip.   If you look at the bottom of them, near the screw holes you will see a set of letters and numbers. That tells the rating of the heater (a chart will show the current range the overloads will trip at).   I think you will find that you have 2 that are of greatly different current ranges. The one with the wire is a much smaller current rating than the large flat one.

DaveC <not@home.cow>: Jun 01 11:13PM -0700 On 1 Jun 2016, Ralph Mowery wrote:   > I think you will find that you have 2 that are of greatly different > current ranges. The one with the wire is a much smaller current rating > than the large flat one.   You are correct! (c;   With the wire: 5.46A; without: 19.8A.   So they are compatible (will work in the same OL)?   Thanks.

Ralph Mowery <rmowery28146@earthlink.net>: Jun 02 10:01AM -0400 In article <0001HW.1D00060A001FD374114D213CF@news.eternal- september.org>, not@home.cow says...   > You are correct! (c;   > With the wire: 5.46A; without: 19.8A.   > So they are compatible (will work in the same OL)?   The main overload block is made to take a wide range of the heaters. It has been a while ( I retired about 4 years ago) but I think there were atleast 2 to 5 sizes of the GE overload blocks. The heaters from one size will not fit the other sizes. Each block will hold a lot of different size heaters.   The way they are most often uses is that you have the motor starter (relay) mounted vertically and the heater block is attached just under it. The heater goes from the bottom contacts of the starter through the heater and then out to the motor (load). You install the heater to match the current of the load.   The heater heats up something in that block that trips a switch in the block. That switch is in series with the motor starter coil and the stop/start switches and only carries the small current that activates the coil. Most often the motor will be 480 volts 3 phase and the voltage for the coil and switch will be 120 volts.   While the numbers I am giving out are made up as I don't want to look them up, you may have a size 1 starter rated from 1/2 amp to 30 amps, a size 2 rated from 20 to 50 amps, and so on. You install the heaters in that range to match the load.

jurb6006@gmail.com: Jun 02 02:56AM -0700 Good that you recognize that as cascode. I've ran into techs all over the place who have no clue what that is and think you are making a mistake and mean cascade. (as of now I can tell you my spellcheck does not now WTF cascode is)   Anyway I had to pull the Tek off the bench for a bit to do a Luxman R-117. Healthy receiver really. Thought maybe it was BFC but it's 160 a channel and built for it. But I am back on it next time I go down there.   But anyway, that is pretty much the word - cascode. Used to get the maximum voltage gain.   Usually it has a very high output impedance but they way they got it the transistor is just pulsed I think. It is like Q 4565 is used as a comparator. It would have to be because it appears to feed the R/C network created by the time/div switch.   The more I work on Teks, the more I am impressed with their designing skill. I have never seen anything like it, it is almost scary. Like now, I am going to look into whatever specs I can get on Q 4565 before I just stick something in there.   I got a 561A that was built before I was born and the technology in it is amazing. I got the good plugins for it too, dual time base and dual trace. And almost all tube. In fact I think it may predate tunnel diode triggering. I mean, it may predate tunnel diodes :-)   And mine has a very strong CRT with no screen burn at all.   Anyhow, I think the main thing I need in this transistor is high gain. Voltage and current requirements are minimal. Frequency response should not be much of a problem these days. Since all it does is pulse, even if the ft of the replacement is up in the gigahertz there should be no problem.   I'll keep y'all posted.   And thanks.

JC <Chipbee40_SpamNo@yahoo.com>: Jun 02 08:55AM -0400 > Anyway, since the intensify function works off the ten turn pot pretty much correctly, but the intensified part never ends of course because B sweep doesn't start, that localizes the problem. Like I said, Q4565.   > Thanks...   > Now I just hope that fucker ain't germanium !   this might help you :   http://www.reprise.com/host/tektronix/reference/transistor.asp   2n918

"None" <none@nospam.org>: Jun 01 06:28PM -0400 <thekma @ gmail.com > wrote in message news:9ce88f9c-bdbd-4afd-a94c-a30fc847c862@googlegroups.com... >>what it is sent. "   > "Why wouldn't they send it ? "   > sigh... Simple:   Not as simple as you say.   > The color gamut triangle of > the ATSC *standard* - what the STANDARD > is capable of reproducing -   ATSC has no standard color gamut. Even with caps-lock, there is no STANDARD color gamut in ATSC. Rec. 709 is common for HD programming, and Rec. 601 is common with SD. But ATSC doesn't care; the primaries and the white point are specified in the stream. Maybe someday Rec, 2020 will be standard in a future version of ATSC, but for now, there is no such thing as an ATSC standard color gamut.

thekmanrocks@gmail.com: Jun 01 07:22PM -0700 .... wrote: "STANDARD color gamut in ATSC. Rec. 709 is common for HD programming, and Rec. 601 is common with SD. But ATSC doesn't care; the primaries and the white point are specified in the stream. Maybe someday Rec, 2020 will be standard in a future version of ATSC, but for now, there is no such thing as an ATSC standard color gamut. - show quoted text -"   Butt the f out!   Find someone worthwhile to stalk. Like someone you actually know.

"None" <none@nospam.org>: Jun 01 10:40PM -0400 <thekmanrocks@gmail.com> wrote in message news:66cb8f8a-c517-49c9-8baf-4f2e29aea8d5@googlegroups.com...   > Butt the f out!   > Find someone worthwhile to stalk. > Like someone you actually know.   Sorry to disturb you with the simple facts concerning color gamuts in video standards. But there is no ATSC color gamut standard. NTSC has a very broad gamut, but NTSC is dead. Pointer's gamut is probably adequate for practical use. But ATSC doesn't care. It expect the primaries and white point to be specified in the stream; it's doesn't define them as a standard.   You are obviously way too smart to understand that. Primary colors. White point. Pretty simple stuff.   HFCUIS. LKF. FCK,WAFA. AASBDF. OK, li'l buddy?

isw <isw@witzend.com>: Jun 02 12:35AM -0700 In article <6f135efd-c02a-413c-bfcd-f9aab8a188cc@googlegroups.com>, > burst or even make the PLL in the TV have a phase error because part of the > burst is cut off. However it happened, you sometimes needed to adjust the > tint in the old days.   The Phase Alternation dropped the lowest interlace rate from NTSC's ~15 Hz to ~6.25 Hz, which is really visible and was responsible for PAL's well known "high brightness flicker".   > Also, PAL was more lines. I think it was 50 Hz which would mean they needed a > longer persistence phosphor. Also the horizontal rate was faster. They had > quite a bit more resolution bt at the cost of frame rate.   Higher spatial resolution, lower temporal resolution. Probably a wash.   > But that can be dealt with, you know movies in the theaters only used to be > 24 frames per second right ?   Actually, 48 FPS as projected -- each frame was shown twice.   > Well people did not really have a problem with > that. They only reason it is a problem with a CRT is because the picture is > drawn in a series of lines and that makes it more visible.   It's actually just because it's a much lower rep rate. See my comment on PAL's interlace problem. A longer persistance phosphor would have helped the flicker problem, but would have caused motion blur.   Isaac

jurb6006@gmail.com: Jun 02 02:33AM -0700 >"Actually, 48 FPS as projected -- each frame was shown twice. "   Didn't know that. Makes sense though.   I busted "them". I believe it was a commercial for a Sharp camcorder with good low light capabilities. They were showing what was ostensibly some kids birthday party or something. Well back then I always had six or seven head VCRs. I could tell when they pulled it down from the 48 Hz to 60 Hz. They showed each from twice but every so many cycles they would show it thrice.   The video the showed was clearly on film because a camcorders does not use 24 FPS. (or 48)   Nothing happened, WTF. I didn't buy one, I didn't initiate a class action lawsuit, in fact it is almost like who cares.   Like now, I work on "pro" audio. Know what "pro" actually means here ? It means that the FTC and IHF standards do not apply. You got an amp the has 55 volt rails which yields about 100 WPC but they can call it 3,500 watts. Technical Pro is one of the worst offenders but I have seen worse. I saw one amp supposedly 1,000 watts that had a single TO-220 type chip output. There is no way this thing was even 100 WPC.   But anyway, it is not the same with a DVD, with a good four (plus two audio) head VCR going frame by frame you can see the effect. Two frames would be the same and then three frames would be the same. And I am probably the only person in the world who knows they cheated.   Technically, if their camcorder would work in as low light as that film it was not false advertising, and I really don't recall them saying the video was taken with their camcorder. But the implication was pretty strong. Come on, they are advertising a camcorder with good low light sensitivity, What does the viewer think when he sees a kids birthday party ?   Just another example of the shit they can get away with. But the bottom line is I am so close to not giving a shit I can smell it.

Danny DiAmico <dannydiamico@yahoo.com>: Jun 01 10:35PM The rebuilt motor control board is still working great. So, the solution when you have the F28 communications error is to check the blue wires between the computer control unit and the motor control unit and to check the motor control unit for black burnt spots.

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