OT need long range (>500 ft) wireless simple transceiver (or one-way acceptable) modules
Up at the farm this weekend I discovered that the water pump had been running all the time for who knows how long, overflowing the storage tank and wasting electricity. Normally, the level is controlled by a Clay valve at the tank, which is a float actuated pilot valve that just shuts off the flow, and the pump control end senses the stall pressure and shuts it off. There is no electric power available at the tank, some 400-500 feet away from the house and water pump. I rebuilt the valve a few years ago, and at that time I started looking into remote communication, figuring to build a simple system with a small solar PV panel and SLA battery for power at the tank, a float switch, and some kind of ISM transceiver set to span the distance. I even found some good candidate TXRX modules online, but they now appear to be long obsolete and not available anymore. These were nice and simple, with just a few data lines that could be set at either end, and replicated at the opposite end. I revisited this a couple years ago, and couldn't find anything like what I wanted - only fancy ones like for internet protocol and such.
Does anyone know of any good old fashioned simple signalling module sets (that are available) that would do the job? The simplest would be just half-duplex, even one bit OOK, to say for instance, "water too low, turn on pump." More bits and full duplex would offer more control options and status monitoring. I don't want any PC or uP stuff involved - just something that runs when turned on, and conveys the bits, for this very simple operation.
For now, I've had to shut down the pump, and next time up here will look at fixing the valve again, so it's time to find something I can put together fairly quickly and get the electronic RC option going.
Please reply off-list only.
Ed
|
Re: 2465 Badge Picture Request
|
Re: P6137 probe parts wanted
Thanks, and good points ¡ª I¡¯ll keep my eye out for better probes in original condition.
toggle quoted message
Show quoted text
David:
I have used and collected TEK probes for decades
My favorites are indeed P6137 and P6136, for 10X and Zo.
1/ With great patience its possible to locate mint perfect probes in original TEK case or pouch with all bits.
Have paid $30..$75 worth it!
2/ Suggest to Use ONLY epay USA sellers and avoid Chinese and dealers.
We got some from Ham Radio fleas and Silent Keys.
3/ For 2465/7/A/B and TEK 7000, these are the best probes.
4/ We have some active probes, FET, differential, and some HV but those are seldom used.
The point is you need to keep searching and have patience to find a great item at a reasonable price...
Bon Chance,
Jon
PS: See the excellent Tek Circuit Concepts book Oscilloscope Probe Circuits for all theory and practice.
|
Re: HELP NEEDED with 465 #1
Thanks Michael,
I will email you as needed, and will update the post as well.
Thank you very much for everything.
Best Regards,
Stephen
|
Re: HELP NEEDED with 465 #1
Stephen,
Getting the vertical board out to access the HV Multiplier is really not that bad. I have had several 465's apart in the past few months to replace the probe coding lamps. Take pictures of the coax connections and the other connections and you will be fine. You can do this without removing the Interface board, just loosen the various screws that secure the board and flex it up just enough to clear those two studs that protrude from the HV multiplier. You may also cut the HV lead off flush with the side of the multiplier case, so avoiding problems getting that HV conductor and connector out from under the CRT. Cutting it off will still allow ample material remaining to use on your newly constructed Multiplier. Some of the screws are a bit fiddly to get out and in, but nothing that you can't handle. Feel free to PM me with questions or comments.
--
Michael Lynch
Dardanelle, AR
|
Re: Interpreting Transistor Curve Traces
Yup
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of n4buq Sent: Tuesday, May 31, 2022 12:14 PM To: tekscopes < [email protected]> Subject: Re: [TekScopes] Interpreting Transistor Curve Traces Thanks, Ross. I'll check that out as well. Thanks, Barry - N4BUQ ----- Original Message ----- From: "si_emi_01" <wellington@...>
To: "tekscopes" <[email protected]>
Sent: Tuesday, May 31, 2022 1:02:47 PM
Subject: Re: [TekScopes] Interpreting Transistor Curve Traces Hi Barry,
Another good reference for using a Curve Tracer is:
Tektronix Measurement Concepts
Tektronix - Semiconductor Device Measurement - 1970 (062-1009-00)
It's available on the TekWiki at:
Ross
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of n4buq
Sent: Tuesday, May 31, 2022 10:45 AM
To: tekscopes <[email protected]>
Subject: Re: [TekScopes] Interpreting Transistor Curve Traces
I see where the manual covers this so I'll study on that before asking
more questions.
Thanks,
Barry - N4BUQ
----- Original Message -----
From: "n4buq" <n4buq@...>
To: "tekscopes" <[email protected]>
Sent: Tuesday, May 31, 2022 10:10:51 AM
Subject: Interpreting Transistor Curve Traces Now that I've had some time to accustom myself with my 7CT1N, while I
can make lots of pretty pictures, I'd like a better understanding of
what information I can glean from the results, particularly for
bipolar transistors
From what I understand, STEP AMPLITUDE is an indicator of fixed base
current per step and the AMPERES/DIV determines the vertical scaling.
If the STEP AMPLITUDE is set to 10uA and the AMPERES/DIV is at 10mA,
if I display just two traces and the vertical spacing of the linear
portions of the horizontal lines is 1 division, I presume that
indicates the transistor's current gain is 10mA/10uA = 1000. Is that correct?
Also, I'm curious as to how to properly set this up with the tracer
in a horizontal slot and using a vertical amplifier. With this
configuration, I can change the vertical attenuation as I want and,
thus, am not sure how to calculate a proper vertical AMPERES/DIVISION
value. Using it in the reverse way (the tracer in a vertical slot
and a time-base capable of acting as an amplifier in a horizontal
slot or just an ordinary amplifier in a horizontal slot), I don't
have control over the vertical attenuation and I presume the
AMPERES/DIVISION is direct-reading but that might not be correct.
Apologies if this is extremely basic information that should be
obvious to me by now.
Thanks,
Barry - N4BUQ
|
Re: Interpreting Transistor Curve Traces
Thanks, Ross. I'll check that out as well.
Thanks,
Barry - N4BUQ
toggle quoted message
Show quoted text
----- Original Message ----- From: "si_emi_01" <wellington@...>
To: "tekscopes" <[email protected]>
Sent: Tuesday, May 31, 2022 1:02:47 PM
Subject: Re: [TekScopes] Interpreting Transistor Curve Traces Hi Barry,
Another good reference for using a Curve Tracer is:
Tektronix Measurement Concepts
Tektronix - Semiconductor Device Measurement - 1970 (062-1009-00)
It's available on the TekWiki at:
Ross
-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of n4buq
Sent: Tuesday, May 31, 2022 10:45 AM
To: tekscopes <[email protected]>
Subject: Re: [TekScopes] Interpreting Transistor Curve Traces
I see where the manual covers this so I'll study on that before asking more
questions.
Thanks,
Barry - N4BUQ
----- Original Message -----
From: "n4buq" <n4buq@...>
To: "tekscopes" <[email protected]>
Sent: Tuesday, May 31, 2022 10:10:51 AM
Subject: Interpreting Transistor Curve Traces Now that I've had some time to accustom myself with my 7CT1N, while I
can make lots of pretty pictures, I'd like a better understanding of
what information I can glean from the results, particularly for
bipolar transistors
From what I understand, STEP AMPLITUDE is an indicator of fixed base
current per step and the AMPERES/DIV determines the vertical scaling.
If the STEP AMPLITUDE is set to 10uA and the AMPERES/DIV is at 10mA,
if I display just two traces and the vertical spacing of the linear
portions of the horizontal lines is 1 division, I presume that
indicates the transistor's current gain is 10mA/10uA = 1000. Is that correct?
Also, I'm curious as to how to properly set this up with the tracer in
a horizontal slot and using a vertical amplifier. With this
configuration, I can change the vertical attenuation as I want and,
thus, am not sure how to calculate a proper vertical AMPERES/DIVISION
value. Using it in the reverse way (the tracer in a vertical slot and
a time-base capable of acting as an amplifier in a horizontal slot or
just an ordinary amplifier in a horizontal slot), I don't have control
over the vertical attenuation and I presume the AMPERES/DIVISION is
direct-reading but that might not be correct.
Apologies if this is extremely basic information that should be
obvious to me by now.
Thanks,
Barry - N4BUQ
|
Re: Looking For White Socket Side Covers for 7000 Plugins
Jeff,
I placed an extremely low offer but it expired without response. That might have been a product, though, of the holiday. In reality, I think I would have felt bad to get that merely to rob the covers.
In the meantime, I have sourced a set of replacements from a list member (Tek Museum) and they're on their way so I'm good for now.
BTW, Shapeways offers a new resin(?) that's supposed to be quite strong for thin applications like this. The problem is it would cost $30 each plus shipping - presumably because it's an SLA process. There's another material that uses conventional printing that I thought might also work but it looks like I don't have to worry about it for now. If I were to try this, I think I would beef the thicknesses just a bit. While not too much, there's room to do that for all three walls without causing an interference so this might still work.
Thanks,
Barry - N4BUQ
toggle quoted message
Show quoted text
----- Original Message ----- From: "Jeff Dutky" <jeff.dutky@...>
To: "tekscopes" <[email protected]>
Sent: Tuesday, May 31, 2022 12:04:31 PM
Subject: Re: [TekScopes] Looking For White Socket Side Covers for 7000 Plugins Barry,
I know exactly the listing you are referring to. It's a 3-slot board (Tek PN
672-0043-00), and the seller has four of them. The seller looks like a surplus
parts dealer, and has thousands of items for sale. I wonder how they would
respond to a really low-ball offer. My instinct says that a seller like this
should just want to move stuff, and may respond even to extremely low offers,
but we all know that some sellers are just convinced that their pile of garbage
is actually gold (or that they will luck into a buyer with more money than
sense).
In case you have not seen it, this page on the TekWiki has an excellent
discussion of different ways to repair these card edge sockets
I hold out hope for 3D printing replacements as well, but other folks on this
list, with much more experience, have repeatedly said that it's not practical,
and I do not doubt them (at least not with current 3D printing technology). Of
course I'm not trying to discourage you from trying: technology progresses, and
even if it's not practical today, it will certainly become practical eventually
(for values of "eventually" approaching infinity).
-- Jeff Dutky
|
Re: P6137 probe parts wanted
David:
I have used and collected TEK probes for decades
My favorites are indeed P6137 and P6136, for 10X and Zo.
1/ With great patience its possible to locate mint perfect probes in original TEK case or pouch with all bits.
Have paid $30..$75 worth it!
2/ Suggest to Use ONLY epay USA sellers and avoid Chinese and dealers.
We got some from Ham Radio fleas and Silent Keys.
3/ For 2465/7/A/B and TEK 7000, these are the best probes.
4/ We have some active probes, FET, differential, and some HV but those are seldom used.
The point is you need to keep searching and have patience to find a great item at a reasonable price...
Bon Chance,
Jon
PS: See the excellent Tek Circuit Concepts book Oscilloscope Probe Circuits for all theory and practice.
|
Re: Interpreting Transistor Curve Traces
Hi Barry,
Another good reference for using a Curve Tracer is:
Tektronix Measurement Concepts
Tektronix - Semiconductor Device Measurement - 1970 (062-1009-00)
It's available on the TekWiki at:
Ross
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected] < [email protected]> On Behalf Of n4buq Sent: Tuesday, May 31, 2022 10:45 AM To: tekscopes < [email protected]> Subject: Re: [TekScopes] Interpreting Transistor Curve Traces I see where the manual covers this so I'll study on that before asking more questions. Thanks, Barry - N4BUQ ----- Original Message ----- From: "n4buq" <n4buq@...>
To: "tekscopes" <[email protected]>
Sent: Tuesday, May 31, 2022 10:10:51 AM
Subject: Interpreting Transistor Curve Traces Now that I've had some time to accustom myself with my 7CT1N, while I
can make lots of pretty pictures, I'd like a better understanding of
what information I can glean from the results, particularly for
bipolar transistors
From what I understand, STEP AMPLITUDE is an indicator of fixed base
current per step and the AMPERES/DIV determines the vertical scaling.
If the STEP AMPLITUDE is set to 10uA and the AMPERES/DIV is at 10mA,
if I display just two traces and the vertical spacing of the linear
portions of the horizontal lines is 1 division, I presume that
indicates the transistor's current gain is 10mA/10uA = 1000. Is that correct?
Also, I'm curious as to how to properly set this up with the tracer in
a horizontal slot and using a vertical amplifier. With this
configuration, I can change the vertical attenuation as I want and,
thus, am not sure how to calculate a proper vertical AMPERES/DIVISION
value. Using it in the reverse way (the tracer in a vertical slot and
a time-base capable of acting as an amplifier in a horizontal slot or
just an ordinary amplifier in a horizontal slot), I don't have control
over the vertical attenuation and I presume the AMPERES/DIVISION is direct-reading but that might not be correct.
Apologies if this is extremely basic information that should be
obvious to me by now.
Thanks,
Barry - N4BUQ
|
Re: HELP NEEDED with 465 #1
Michael,
I was hoping to avoid it, but I guess I¡¯m gonna have to make use of one of those HV enclosures after all. I¡¯m already dreading taking apart those boards¡
Best Regards,
Stephen
|
Re: HELP NEEDED with 465 #1
Stephen,
Yes, the HV multiplier is dead (i.e "shorted"). I did not recognize that "wire" sticking up vertically as a jumper. Should have know that was the end of the jumper.
--
Michael Lynch
Dardanelle, AR
|
Re: Looking For White Socket Side Covers for 7000 Plugins
CORRECTION: the part number in the eBay listing is actually for the white socket side covers. I'm not sure what the part numer of the main interface board is (it's not shown in the pictures. There are two daughter boards: a trigger select board with part number 670-1371-03, and a vertical interface board with part number 670-1373-06. Both of these are listed in the 7603 service manual. Considering that complete 7603s are plentiful and cheap on eBay, the asking price for these boards, even "NEW OLD STOCK" is plainly ridiculous.
-- Jeff Dutky
|
Re: 2465 Badge Picture Request
I uploaded a photo of the badge on my 2465 at /g/TekScopes/album?id=275497 It's pretty good and could be made better with a little touch up using a photo editing program. Cheers, Tom
|
Re: Looking For White Socket Side Covers for 7000 Plugins
Barry,
I know exactly the listing you are referring to. It's a 3-slot board (Tek PN 672-0043-00), and the seller has four of them. The seller looks like a surplus parts dealer, and has thousands of items for sale. I wonder how they would respond to a really low-ball offer. My instinct says that a seller like this should just want to move stuff, and may respond even to extremely low offers, but we all know that some sellers are just convinced that their pile of garbage is actually gold (or that they will luck into a buyer with more money than sense).
In case you have not seen it, this page on the TekWiki has an excellent discussion of different ways to repair these card edge sockets
I hold out hope for 3D printing replacements as well, but other folks on this list, with much more experience, have repeatedly said that it's not practical, and I do not doubt them (at least not with current 3D printing technology). Of course I'm not trying to discourage you from trying: technology progresses, and even if it's not practical today, it will certainly become practical eventually (for values of "eventually" approaching infinity).
-- Jeff Dutky
|
Re: Interpreting Transistor Curve Traces
I see where the manual covers this so I'll study on that before asking more questions.
Thanks,
Barry - N4BUQ
toggle quoted message
Show quoted text
----- Original Message ----- From: "n4buq" <n4buq@...>
To: "tekscopes" <[email protected]>
Sent: Tuesday, May 31, 2022 10:10:51 AM
Subject: Interpreting Transistor Curve Traces Now that I've had some time to accustom myself with my 7CT1N, while I can make
lots of pretty pictures, I'd like a better understanding of what information I
can glean from the results, particularly for bipolar transistors
From what I understand, STEP AMPLITUDE is an indicator of fixed base current per
step and the AMPERES/DIV determines the vertical scaling. If the STEP
AMPLITUDE is set to 10uA and the AMPERES/DIV is at 10mA, if I display just two
traces and the vertical spacing of the linear portions of the horizontal lines
is 1 division, I presume that indicates the transistor's current gain is
10mA/10uA = 1000. Is that correct?
Also, I'm curious as to how to properly set this up with the tracer in a
horizontal slot and using a vertical amplifier. With this configuration, I can
change the vertical attenuation as I want and, thus, am not sure how to
calculate a proper vertical AMPERES/DIVISION value. Using it in the reverse
way (the tracer in a vertical slot and a time-base capable of acting as an
amplifier in a horizontal slot or just an ordinary amplifier in a horizontal
slot), I don't have control over the vertical attenuation and I presume the
AMPERES/DIVISION is direct-reading but that might not be correct.
Apologies if this is extremely basic information that should be obvious to me by
now.
Thanks,
Barry - N4BUQ
|
Re: HELP NEEDED with 465 #1
|
Re: HELP NEEDED with 465 #1
On Tue, May 31, 2022 at 05:41 PM, Michael W. Lynch wrote: Interleaved. Stephen,
The crackling noise does not come from the back of the CRT. I can actually see
(and hear) the small arcing beneath the board, circled in red in the picture:
That is the ground connection for the HV Multiplier. That is
part of your issue. That is normally soldered to connect HV Multiplier ground
to the PCB ground trace. Without that ground, the HV multiplier will not work
correctly. Fix that first, then see what happens. Michael, That solder joint circled in red in the picture, under which the arcing could be seen, was not grounded. You said that this is the HV ground. And sure enough, I checked the other 465, and that joint is grounded. The loose wire is a ground connection, and is the correct length to be soldered to that point. It¡¯s probably where it must¡¯ve been in the first place. I reattached it. There is no more crackling noise when the Beam Finder is pushed. However, it¡¯s now not working anymore. There is no trace whatsoever either. All the voltages are still perfect, except for the HV. It¡¯s now down to -750V. I guess that means the HV multiplier is indeed dead¡???? Best Regards, Stephen
|
Re: HELP NEEDED with 465 #1
On Tue, May 31, 2022 at 10:23 AM, Stephen wrote:
If the HV Multiplier has "failed open" it might allow the -2450 to
remain unaffected.
But in the case of a shorted or opened HV multiplier, would I have the Beam
Finder working, or even something showing on the CRT?
If there is any "crackling" noises, it could be a loose
CRT anode connector or and extremely dirty CRT causing arcing. Is the area
under the HV Guard cover on the interface board "very dirty?
I cleaned it quite extensively as best I could without removing the CRT
itself.
The crackling noise does not come from the back of the CRT. I can actually see
(and hear) the small arcing beneath the board, circled in red in the picture:
/g/TekScopes/photo/275495/3437708?p=Created%2C%2C%2C50%2C2%2C0%2C0
You¡¯ll also notice a solid wire hanging upright loose with nothing attached
to it. It apparently had something soldered to it at some point (I can see the
remnants of a wire). But I can¡¯t figure out what it was. It is a ground
wire.
If the Intensity cannot be controlled, then you could have issues with the
Z-axis
circuitry or the DC Restorer,
DC restorer?
All the transistors in the Z-Axis circuitry check ok. I haven¡¯t checked
anything else there.
Stephen, The crackling noise does not come from the back of the CRT. I can actually see
(and hear) the small arcing beneath the board, circled in red in the picture:
That is the ground connection for the HV Multiplier. That is part of your issue. That is normally soldered to connect HV Multiplier ground to the PCB ground trace. Without that ground, the HV multiplier will not work correctly. Fix that first, then see what happens. But in the case of a shorted or opened HV multiplier, would I have the Beam Finder working, or even something showing on the CRT?
If the HV Multiplier is OPEN, the CRT and beam finder will show activity. If SHORTED, this will take out the -2450 and you get nothing. With the previous issue of the "bad ground" mentioned above, your HV multiplier is acting as if it is OPEN. That "Extra" wire, I have no idea, perhaps a test point for some previous repair? . Do you have a Service manual? In the Circuit Description there is a section that describes the DC Restorer. Review this section for a better understanding. The DC Restorer is diode based, not transistor based, so you are not testing the parts that typically fail. -- Michael Lynch Dardanelle, AR
|
Re: HELP NEEDED with 465 #1
On Tue, May 31, 2022 at 04:54 PM, Michael W. Lynch wrote:
You do not mention if there is any vertical deflection in response to an input
signal. What happens if you apply a signal to either input channel?
--
Michael Lynch
Dardanelle, AR
I haven¡¯t tried inputting any signals yet. Will do though. Best Regards, Stephen
|
Michael W. Lynch
Jean-Paul
Tom Phillips