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Re: Manual for a Telequipment S61?
I have manuals for S51 if you think they may be similar.
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Glenn On 5/9/2021 12:11 PM, Liam Perkins wrote:
I can't find a manual for a Tele' S61 anywhere and the TekWiki download --
----------------------------------------------------------------------- Glenn Little ARRL Technical Specialist QCWA LM 28417 Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178 QTH: Goose Creek, SC USA (EM92xx) USSVI, FRA, NRA-LM ARRL TAPR "It is not the class of license that the Amateur holds but the class of the Amateur that holds the license" |
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Re: GPIB board for calibrating AM503B, or alternatives?
Hi Jared,
I have 3 of these GPIB adapters (have 3 x AM5030B). I wanted to program the serial number and it didn't work. So I connected a logic analyzer to see what was going on. If you only want to update the calibration data, you can program the addresses 0xE0-00xE1 (CALC 00 or RinX1 value), 0x0B-0X0C (CALC 01 or RinX10 value) and 0xCA-0xCB (CALC 02 or RinX100 value) in the PCF8570 (Base address= 0xA0) on the I2C bus with "Bus Pirate". The calibration data are stored there. After changing the battery, 0x61A8 (= 25000) remains there. Best regards Rico |
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Re: 7M13 buttons
Hi Esmond,
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I just checked every one of about 50 push button switch assemblies I have removed from 7000 series parts mules. I never noticed this before now, but every single one latches. The only exception to this seems to be the push button you press when you want a Single Sweep on the time base plugins. The only plugins that don't use any latching push buttons are the programmable 7000 plugins like the 7A16P, 7A29P and 7B90P, and the 7D20. Also the DF1 and DF2 formatters for the 7D01 don't use the latching push buttons. I don't have any of these that I can use for parts mules Some of the newer TM5000 plugins which are programmable don't have latching plugins. For example, the FG5010 and SG5010 switches that you press to specify the frequency you want them to generate, are momentary. I don't have any of these that I can use for parts mules. Dennis -----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of EJP Sent: Saturday, May 08, 2021 9:37 PM To: [email protected] Subject: Re: [TekScopes] 7M13 buttons Sadly the 7A12 parts Dennis mentioned are not the same. Very sad as I had found a source for them new here: . 1. The buttons on the 7A12 parts are latching where the 7M13 buttons aren't. This may or may not be a showstopper, as the 7M13 has electronic latching, but the physical latching may interfere with that. 2. The plastic rivets that retain the PCB to the switch body are in different places. Again not insurmountable but an issue. 3. Showstopper is that the electrical contact layout is different, so the 7M13 PCB does not electrically marry up to the 7A12 switches. In other words the switch assemblies are definitely different. This is also visible at the inside ends of the switches, which look quite different in each case. For the record here is the 7M13 disassembly procedure I used. 1. Prise off the front panel of the 7M13 with a small screwdriver head, starting from the bottom centre, and clearing the latch tag. 2. Remove the nut and washer from the camera trigger connector. 3. Remove the 4 screws at the back end securing the interface slotting to the chassis. Remove one screw securing the PCB to a flange near the front. You don't need to remove the spacer between the main PCB and the motherboard. 4. Partially withdraw the main PCB and the motherboard to the rear, far enough so you can pull the motherboard up and out of the chassis while leaving it connected to the main PCB. You need the motherboard up and out of the way for the next step. It only comes out one way, due to the flange mentioned above. This process will release several dozen pin-and-sleeve connections from the motherboard to the switch assemblies. 3. At the front, remove the three screws from the switch assembly you want to repair. Do this wth the chassis vertical, standing on its rear end, so as not to lose the screws. The assembly should now drop out. 4. At this point you can either remove the PCB from the switch assembly and move it to a new one, or else 3D-print and glue on some short rectangular-section extenders for the broken button(s). I will do the latter, after filing the broken surface a bit flatter for better adhesion. If you remove the PCB, DO NOT unsolder anything, as this will loosen ten delicate contact mechanisms that would otherwise just come out with the PCB, which is a better option. Just gently apply heat from a heat gun to the round black plastic rivet heads while levering upwards against them until the PCB pops off each one in turn. This is surprisingly easy. When replacing, apply heat the same way to re-melt the rivet heads. (You could in theory do the gluing after step 1 without removing anything but the front plate. but you'd be running a lot of risk of getting the glue into unwanted places.) 5. Reassembly is the reverse of the above. Have fun getting all the motherboard pins in at the same time ;-) Thanks to Dennis for the assistance. EJP -- Dennis Tillman W7pF TekScopes Moderator |
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Re: Manual for a Telequipment S61?
S61B and maybe another lead
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On Sun, May 9, 2021 at 9:47 AM Liam Perkins <hifi@...> wrote:
Thanks but that the same D61A manual that's everywhere else. All the nice |
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Re: Tek 22XX Fans
Hi,
I repaired several 2213, 2215 and 2235 scopes, and with all of them I added the fan. It's a simple 60x60mm 12VDC fan, and with most of the main PCB's the print already has place to put the one resistor, one diode and one capacitor. I do this because the main course if failure is the secondary switcher, and sometimes the transformer. Recently I worked on a 2236, and that one had the fan already. Direction of the airflow is from the inside towards the outside of the scope. Un saludo, Leo |
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Tek 22XX Fans
Roy Morgan
Tek Folks,
Mu 2215A has a fan-like exit port at the back. Does it have a fan? If not, does it need one? If so, I assume there are list threads about it. (I have not taken it out of the case to find out.( Roy On May 9, 2021, at 11:42 AM, satbeginner <castellcorunas@...> wrote:Re: [TekScopes] Problems with t935a HV supply ... The new one (HV transformer) performed perfectly, so I added the fan ( as in many 22xx scopes) and performed a full calibration. Roy Morgan K1LKY since 1958 k1lky68@... Western Mass |
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Re: Manual for a Telequipment S61?
Liam Perkins
Thanks but that the same D61A manual that's everywhere else. All the nice
folks don't seem to be paying attention. On Sun, May 9, 2021 at 10:26 AM Geoffrey Thomas via groups.io <geoffreythomas@...> wrote:
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Re: Manual for a Telequipment S61?
Geoff. On 09/05/2021 17:11, Liam Perkins wrote:
I can't find a manual for a Tele' S61 anywhere and the TekWiki download |
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Re: Problems with t935a HV supply
What you're doing, I think, is to shock excite the winding. Ideally, you'd use a unit impulse, but a short pulse may work just as well.? The frequency of the waveform simply allows the system to ring until it naturally damps.? Too fast and you'll not see the whole pulse train.? The AC signal will likely give you the ratios, but not an idea of loading/shorts.? For this test, you actually do want those high frequency harmonics so the winding is shock excited.
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Some of the Sencore capacitor testers also have a ringing test available for inductors. Harvey On 5/9/2021 11:22 AM, - wrote:
What is the normal operating frequency of that transformer? 1000 Hz test |
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Re: TM-500 Test Module Question
Hi Jared,
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I have just taken a look at the photos of the plug-in tester on Tekwiki and it looks rather like the BNC shell is connected to the ground simply by virtue of the fastening to the aluminium front panel. Take a look here: I think I should have taken a look at this earlier... I recall also that Dave Casey of this Forum has an original which he says looks exactly like the one on Tekwiki. Perhaps he could be persuaded to check if his BNC shell is grounded at all of the switch positions? Colin. -----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Jared Cabot via groups.io Sent: 09 May 2021 16:35 To: [email protected] Subject: Re: [TekScopes] TM-500 Test Module Question Hmm, ok. Now I'm second guessing myself here. :D When I designed my unit, I had interpreted from the original manual that the BNC was connected across the HI and LO terminals, like the multimeter when connected. Now I'm not so sure.... It's not a big deal to configure one way or another, either isolate the BNC shell from chassis and install the wire to the PCB for connection to the LO terminal, or remove the wire and connect the BNC to the chassis. I think I'll do some testing in each configuration and see what works best. I have a couple TM501 mainframes on my bench ready to be tested right now by chance. |
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Re: Problems with t935a HV supply
Hi,
No, once I confirmed by the ringing test it was bad, my guess would be the HV winding. I tried to take it apart to see if a (partial) rewind would be possible, but it was impregnated solid, so a rewind was a no-go. The new one performed perfectly, so I added the fan ( as in many 22xx scopes) and performed a full calibration. Leo |
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Re: Problems with t935a HV supply
Leo,
I see that you took the x-former in your pictures apart. Did you ever determine what the internal failure mode was? General comment. As Leo's pictures show, transformer failures can be tough to diagnose since they frequently still have an output but just not the correct output. And if you don't know exactly what the output waveform is supposed to look like, or how long the output signal is supposed to ring, then you could overlook the failure. This type of mis-diagnoses was common when automobiles were still using a Kettering ignition system. On Sun, May 9, 2021 at 11:22 AM satbeginner <castellcorunas@...> wrote: Hi, |
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Re: TM-500 Test Module Question
Hmm, ok. Now I'm second guessing myself here. :D
When I designed my unit, I had interpreted from the original manual that the BNC was connected across the HI and LO terminals, like the multimeter when connected. Now I'm not so sure.... It's not a big deal to configure one way or another, either isolate the BNC shell from chassis and install the wire to the PCB for connection to the LO terminal, or remove the wire and connect the BNC to the chassis. I think I'll do some testing in each configuration and see what works best. I have a couple TM501 mainframes on my bench ready to be tested right now by chance. |
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Re: Problems with t935a HV supply
What is the normal operating frequency of that transformer? 1000 Hz test
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frequency seems to be on the rather low side. What is the frequency of the ringing that you're seeing? That's probably the resonant frequency of the x-former with it's associated circuitry attached and I would expect to see the X-former normally being operated at about the same frequency. I'm not familiar with the t935 but IMO you'd probably be better off using a very low voltage AC signal instead of a square wave to drive the transformer when testing. Coupling the x-fomer to the signal source through a capacitor should remove most the higher frequency harmonics from the square wave and leave you with mostly the base frequency sine wave. On Sun, May 9, 2021 at 11:03 AM Ham Radio <bernard.murphy@...> wrote:
The ring test with a 10 volt 1000 Hz square wave with a duty cycle of 1% |
satbeginner
Jared Cabot