Panel mount scheme for 128 x 32 0.91" OLED?
Has anyone found an easy way to fit these displays to a panel?? They are small, simple to use and provide a good size display, but have no mounting holes and there is only about 3mm at either end of the glass for adhesive pads - which probably would not last long.? I have not seen one installed in consumer goods to see how they are held in place - maybe dropped into a moulded cavity with hot melt glue to secure?? The components on the back panel preclude a rigid plate.? I have thought about soldering pre-drilled tabs on to the back of the display, but the OLED is fragile, and I would like it to be easy to replace when/if it fails.? (I have been using 128 x 64 versions for years, and have just had to replace one).
The best I have come up with so far is a packing shim round the glass display and a plain pressure panel with resilient foam on the back to hold it in place with screws through both and the front panel, but the shim will be fiddly to make.? Panel thickness will be 1-2mm for different jobs.
I have found only one manufacturer of a bezel, but it is huge and would dominate the planned front panels. ?
Any ideas welcome.
PeterS??? G8EZE
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Re: Heterodyne RF generator
Reg,
Interesting idea. It would require a tracking passband filter as frequency is sweeped, to select the desired harmonic. But I fear you should need to have selected the 15th harmonic in the range of, say, 1500 to 2500MHz and mix it with 1500 fixed, in order to cover 0...1000.
I had thought of something like that but with a single PLL. As varactor tuned filters can't span much more than 1:3 frequency, two or more should have to be switched in and out if 1 or more decades range are needed. There would be an unavoidable amplitude and phase transient during the handoff, sweep should have to be stopped until stabilization, and the detector should have to be instructed to ignore during the transition.
If the transients can be tolerated, e.g. ignoring them by software after the detection, there is another possibility: instead of multiple tracking filters, have multiple VCOs, phase locked to the Si5351 thru programmable dividers
I am thinking while writing... Why not combining both ideas? Get 1500...2500 from a single VCO, phase-lock it to 94...156MHz thru a /16 fixed divider, mix it with 1500 locked from another 5351 output.
Lots of ideas, little free time...
Daniel LW1ECP
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El jueves, 17 de agosto de 2023, 23:17:08 ART, Reginald Beardsley via groups.io <pulaskite@...> escribi¨®:
Daniel,'
As you have an Si5351 I'd like to suggest examining using a fast (e.g. Potato Chip) TTL part with sub 1 ns rise time to increase the harmonic content to over 1 GHz, filtering the unwanted harmonics and. mixing the two Si5351 outputs.? This would require some MCU programming, but my initial examination suggests that with proper choice of frequencies and mixer you could sweep the Si5351 from 10 kHz to 1 GHz with relatively little effort.
I plan to work on the frequency plan some more tomorrow to eliminate some gaps in? my attempts. today.? A tinySWEEPER looks to me to be? a viable Si5351 project from 10-100 khHz TO 1 GHz.? That would be a huge boon to the RF community..
Have Fun!
Reg
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Re: SCPI Command Parser Firmware For Instrument
FWIW
30 years ago I wrote a parser using lex and yacc that ran in production for 8-9 years without a single bug report. It would take some revierw work to do that now, but is there isn't a solution extant, I'd be pleased to write one subject to a very busy schedule. It would be fun to write some software again.
Have Fun!
Regt
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Re: Heterodyne RF generator
Daniel,'
As you have an Si5351 I'd like to suggest examining using a fast (e.g. Potato Chip) TTL part with sub 1 ns rise time to increase the harmonic content to over 1 GHz, filtering the unwanted harmonics and. mixing the two Si5351 outputs. This would require some MCU programming, but my initial examination suggests that with proper choice of frequencies and mixer you could sweep the Si5351 from 10 kHz to 1 GHz with relatively little effort.
I plan to work on the frequency plan some more tomorrow to eliminate some gaps in my attempts. today. A tinySWEEPER looks to me to be a viable Si5351 project from 10-100 khHz TO 1 GHz. That would be a huge boon to the RF community..
Have Fun!
Reg
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Re: Heterodyne RF generator
Daniel,
My mother used to say my father carried a pair of Vise Grips in his pocket to squeeze the pennies and I was the same way until I was in my mid 60s. I literally spent years pondering how to make an SA on the cheap.. Just not as clever as edy555 and Erik. My sister and husband stayed with me for 8-9 months while I worked to make Mom & Dad's house wheelchair accessible. He went downhill so rapidly from Parkinson's associated dementia that I cut my purse strings and now enjoy more high end HPAK & Tek lab gear than I have a place to use it.
My single strongest electronics passion is low cost T&M kit. The tinySA and nanoVNA have fulfilled those needs
The method you describe is how I achieved the filter result shown using a pair of tinySAs.
Most of my electronics efforts were while I was in grad school 35 years ago. All I had was a 5 MHz recurrent sweep Heathkit scope, VOM, DMM and a 5 V supply I built and a 12 V supply I bought for $1 and fixed by replacing the regulator for a total cost of $1.20. I noted that on the bottom of the supply with a marker. I attemtped to build a DC 40 m receiver, but couldn't get a signal. I suspected that the input filter was wrong, but had no way to test it until years later when I picked up a proper scope and an 8601A 100 MHz sweeper.
You are pursuing the same goals as I am. As I have the luxury of a very well equipped RF lab I am focused on testing stuff from China and the performance of my own projects.
Time permitting, I'll attempt to replicate and measure performance as you work on your sweeper design. The easy way would be a pair of AD4351s, mixer and some filters. However, those would cost as much as a nanoVNA. However, they would be more capable.
I have been assembling a large collection of RF modules both from top line US makers and Chinese ebay stuff. The goal is to be able to build any sort of test kit such as a VNA, SA, etc by connecting the right pieces.
Have Fun!
Reg
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Re: Heterodyne RF generator
??
Hi Daniel,
Couple suggestions that may help your project
I second the QRPLabs Ultament U3 plus low pass filters for GPS local oscillator and or rf sweep generator
Along with a common diode es dc meter make a very nice 'calibrated' radio freq power meter
???? https://www.aa5tb.com/qrpmeter.html
Very nice PC soundcard scope es spectrum analyser es sweeper
????? https://www.zeitnitz.eu/scope_en
Of course sub radio frequency but very handy for tuning CW filters
72 73
John
N3AAZ
FM19 on DELMARVA Peninsula
ps...
I too just found this site
If being an 'ole-frt' qualifies to post...hi HI :>)
op 1941
ham 1956
retired 1997
Check my? qrz.com? page for current project
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Re: Heterodyne RF generator
Hello, if I - a fellow old coot - can help by forwarding components from Hungary or Slovakia, let me know. 100g of Components, tracked, from SK is like 5USD shipped. Might beat customs Tam On August 16, 2023 6:01:10 AM GMT+02:00, "Daniel Ricardo Perez via groups.io" <danyperez1@...> wrote:
Reg, thank you for your interest on my topic! I am an old man too (66), I saved as much money as I could too, but the economic situation on my country is bad and I need to keep working after having retired (and I'm lucky I keep a job yet). I do know this is no place to talk politics, but so that you understand me, I am forced to mention the government tries to reduce debt by hindering imports, in a nutshell. If you are interested, I can elaborate more by private email. And most electronics stores don't even know words such as "Amidon", "Minicircuits", "Analog Devices", etc. Their main interest is in sourcing components for digital systems and for repairs. For example, you can easily get Tx transistors just because they die and have to be replaced, BUT toroids never fail, so they aren't a common item. Last but not least, I CAN afford to purchase those little wonders such as NanoVNA or TinySA, but I can't justify them in the face of my family, with a salary a fraction of those in USA or EU, I would use them only occasionally and an anticipated criticism would be why I spend in something that won't make any money. On the other hand, spending money on building or purchasing radios and making communications, a tangible usefulness, would make more sense for them. That said, now you can understand better why I am resorting to old tech solutions. I would also enjoy building every stage. I do know I will face some inconveniences such as MHz versus time nonlinearity, and I will have to use birdy markers in order to find the frequency. One initial use will be to check HF response of DIY wideband transformers, a modest Ge diode detector plus 3/6/10dB attenuator will suffice. But if the opportunity to make more serious measurements ever comes, you can rest assured your advice will be taken very into account! Daniel Perez LW1ECP P.D. Detector? Do you want to know an unusual detector? When I had the Wavetek 2000 at work, in order to get some decades in detection range I used an spectrum analyzer with its sweep frequency very different from that of the sweeper, in peak reading memory mode, and waited for the curve to fill valleys. Crude, a far cry from using a tracking generator, but I could get usable info even about an SSB filter. El martes, 15 de agosto de 2023, 12:18:54 ART, Reginald Beardsley via groups.io <pulaskite@...> escribi¨®: Daniel, A sweeper is of no use without a receiver of some type.? An explanation of your intended use case would be very helpful. My first suggestion for building one would be to use? a pair of AD4351? square wave generators with? switched low pass filters boards? such as the QRP-Labs offering: http://qrp-labs.com/ultimatelpf.html An alternative choice would be an AD4351 and a AD9834 or similar AD based DDS, Sweep the DDS and step the AD4351 after each DDS sweep. I'm very interested in your quest and spent a lot of time pondering the subject before realizing I was now an old man and could buy anything I wanted for the simple reason I saved as much money as I could while I was working.? I'm looking forward to your replies. Have Fun! Reg With best regards Tam HANNA -- Enjoy electronics, 3D printing and cigars? Join more than 21000 followers on my Instagram at
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Re: Heterodyne RF generator
Reg, thank you for your interest on my topic! I am an old man too (66), I saved as much money as I could too, but the economic situation on my country is bad and I need to keep working after having retired (and I'm lucky I keep a job yet). I do know this is no place to talk politics, but so that you understand me, I am forced to mention the government tries to reduce debt by hindering imports, in a nutshell. If you are interested, I can elaborate more by private email.
And most electronics stores don't even know words such as "Amidon", "Minicircuits", "Analog Devices", etc. Their main interest is in sourcing components for digital systems and for repairs. For example, you can easily get Tx transistors just because they die and have to be replaced, BUT toroids never fail, so they aren't a common item.
Last but not least, I CAN afford to purchase those little wonders such as NanoVNA or TinySA, but I can't justify them in the face of my family, with a salary a fraction of those in USA or EU, I would use them only occasionally and an anticipated criticism would be why I spend in something that won't make any money. On the other hand, spending money on building or purchasing radios and making communications, a tangible usefulness, would make more sense for them.
That said, now you can understand better why I am resorting to old tech solutions. I would also enjoy building every stage. I do know I will face some inconveniences such as MHz versus time nonlinearity, and I will have to use birdy markers in order to find the frequency. One initial use will be to check HF response of DIY wideband transformers, a modest Ge diode detector plus 3/6/10dB attenuator will suffice. But if the opportunity to make more serious measurements ever comes, you can rest assured your advice will be taken very into account!
Daniel Perez
LW1ECP
P.D. Detector? Do you want to know an unusual detector? When I had the Wavetek 2000 at work, in order to get some decades in detection range I used an spectrum analyzer with its sweep frequency very different from that of the sweeper, in peak reading memory mode, and waited for the curve to fill valleys. Crude, a far cry from using a tracking generator, but I could get usable info even about an SSB filter.
El martes, 15 de agosto de 2023, 12:18:54 ART, Reginald Beardsley via groups.io <pulaskite@...> escribi¨®:
Daniel,
A sweeper is of no use without a receiver of some type.? An explanation of your intended use case would be very helpful.
My first suggestion for building one would be to use? a pair of AD4351? square wave generators with? switched low pass filters boards? such as the QRP-Labs offering:
http://qrp-labs.com/ultimatelpf.html
An alternative choice would be an AD4351 and a AD9834 or similar AD based DDS, Sweep the DDS and step the AD4351 after each DDS sweep.
I'm very interested in your quest and spent a lot of time pondering the subject before realizing I was now an old man and could buy anything I wanted for the simple reason I saved as much money as I could while I was working.? I'm looking forward to your replies.
Have Fun!
Reg
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Re: Heterodyne RF generator
Daniel,
A sweeper is of no use without a receiver of some type. An explanation of your intended use case would be very helpful.
My first suggestion for building one would be to use a pair of AD4351 square wave generators with switched low pass filters boards such as the QRP-Labs offering:
An alternative choice would be an AD4351 and a AD9834 or similar AD based DDS, Sweep the DDS and step the AD4351 after each DDS sweep.
I'm very interested in your quest and spent a lot of time pondering the subject before realizing I was now an old man and could buy anything I wanted for the simple reason I saved as much money as I could while I was working. I'm looking forward to your replies.
Have Fun!
Reg
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Re: Origins of nanoVNA & tinySA [was: Heterodyne RF generator]
I'm quite aware of the history of the nanoVNA, edy555, Hugen's part and Erik's part. The clone problem is very acute because of the low cost, high performance and popularity. I focused on Erik because he posts a list of authorized sellers. I bought all of mine from R&L
electronics as I am in the USA.
Have Fun!
Reg
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Re: Origins of nanoVNA & tinySA [was: Heterodyne RF generator]
Reginald,
for the sake of accuracy, Erik designed the tinySA, inspired by
the nanoVNA. The nanoVNA itself was originally designed by
eddy555, a Japanese Radio Amateur, whose design was then adopted
& adapted by Hugen, a Chinese Radio Amateur, to become the
pre-built nanoVNA which is available today. And that design itself
has spawned both a wide degree of ownership and the inspiration
for further low-cost VNA designs.
Erik did use the nanoVNA-H4 hardware as the basis for his
tinyPFA.
The hardware of both the nanoVNA (-H and -H4) and the tinySA make
extensive use of SA612 mixers, SA5351A-B-GT frequency
synthesizers, STM32F3xxxx microprocessors, USB powering &
communication, a Lithium cell, and ChibiOS for the firmware, plus
other bits & pieces. That is a very powerful mixture
that can readily be re-purposed, as Erik has demonstrated. [And
other ?processors and OSes are both available and very useful, of
course.]
73, Stay Safe,
Robin, G8DQX
PS: Much more at ,
plus where the links lead.
On 14/08/2023 01:50, Reginald Beardsley
via groups.io wrote:
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Show quoted text
Hi, Daniel,
My first post here also as I just found the list. I strongly recommend a tinySA or nanoVNA H4. Just make sure you don't get a clone. So check the [email protected] list for legit sellers. Erik designed both. They produce a square wave (Si5351), so you need a low pass filter for the band of interest. A 3 element Cauer will suppress all harmonics by -50 dBc or better.
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Re: Heterodyne RF generator
Phooey. Hit the wrong button. Here are sweeps of the 40 m LPF using a pair of tinySAs and a nanoVNA H4.
I have 3x tinySAs and a nanoVNA H and nanoVNA H4. The reason for having so many tinySAs is as signal generators for a Field Day RF bench setup with Owon HDS272S DSO/DMM/AWG, DMM and various mixers, filters and a noise source.
These noise sources are quite good, though I see the price has gone up since I bought mine. They are quite flat out to about 1 GHz according to my HP 8560A.
The BG7TBL noise source is junk. Search on EEVblog using advanced search using "noise source" user rhb and titles only and you should find my test results.
I do quite a bit of testing of low cost RF stuff from China, much of which I have posted to EEVblog "rhb" is my user name. I also post a lot to the qrptech and qex lists.
Have Fun!
Reg
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Re: Heterodyne RF generator
Hi, Daniel, My first post here also as I just found the list. I strongly recommend a tinySA or nanoVNA H4. Just make sure you don't get a clone. So check the [email protected] list for legit sellers. Erik designed both. They produce a square wave (Si5351), so you need a low pass filter for the band of interest. A 3 element Cauer will suppress all harmonics by -50 dBc or better. The photo shows a pair of tinySAs, one as a sweeper and the other as an SA using peak hold. The filter was designed for 40 m. You can get similar results for filters using a nanoVNA H or one of the quality variants. Erik's nanoVNA H4 has the advantage that you can also load FW to do phase and frequency analysis and a larger screen. The particular tests you want to make and your current T&M kit make a proper answer difficult. If you don't have a VNA, which I'd expect to be the case as you are seeking a sweeper without mentioning use case, you absolutely should buy a nanoVNA H or H4.
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Hi,
I am LW1ECP, this is my 1st post. I love to design and build anything at home, my main limitation is lack of time to make solder smoke.
I'd like to build a sweeper for my home bench. I have an unused Si5351 board but it generates squarewaves. I could purchase one based on the AD9851 but its range is more limited. I know there are more advanced alternatives but importing in my country has important restrictions and taxes at present.
Where I worked in the late 70s, I used to play with a Wavetek 2000, a sweep/signal generator covering 0 to 1400MHs in 3 bands. It was based on heterodyning two oscillators. So I thought about building something like that. For now it could cover 0 to 200MHz, with DIY VCOs and mixer.
I got tired of searching the web for something like that.?Trying to duplicate the Wavetek circuit is quite involved. Can anyone point me to a more modest design?
Thank you.
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Re: EMI filtering on power cord
For anyone who wants the complete picture on RFI filtering, and in particular the proper application of ferrites, here is the reference:?
Gary NA6O
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Re: EMI filtering on power cord
Hi Goran
Clamp-on ferrites work as well as the solid ferrite beads, but one big problem has always been the price factor.? These look cheap enough to use,?even though they're more than twice as?much as the ones I referenced. ?
I might get a few dozen of those.
73 Jim N6OTQ ?
On Fri, Aug 4, 2023 at 4:36?AM Goran Finnberg via <mastering= [email protected]> wrote: Jim N6OTQ:
>If your power cord is round and has a diameter of 1/4" or less, these guys will? >work:? < >
>You'll need to cut the cord to get these ferrite beads on, and then splice the cord? >back together?
Instead of cutting the power cord why not use these clamp on devices instead:
I have used the clamp on ferrite devices for more than 30 years now and they are very? good and exceptionally easy to use.
Please, be aware that you can easily put as many as needed on a cable by just putting? them on and on in series to add filtering as needed.
Cheap too.
-------
Best regards,
Goran Finnberg
The Mastering Room AB
Goteborg
Sweden
E-mail: mastering@...
Learn from the mistakes of others, you can never live long enough to
make them all yourself.??? -?? John Luther
(\__/)
(='.'=)
(")_(") Ranglet, Aron, VovVov, Nero & Smurfen:RIP
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Re: EMI filtering on power cord
Sounds good. ? Good luck. ? Ross ?
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Show quoted text
From: [email protected] < [email protected]> On Behalf Of Radu Bogdan Dicher Sent: Friday, August 04, 2023 10:52 AM To: [email protected]Subject: Re: [Test Equipment Design & Construction] EMI filtering on power cord ? Further thanks to all that pitched in. As usual, a side conversation at least as interesting is?unfolding.? On my side of things, I've grabbed a box of assisted?clamp-on ferrites from AMZ (can be had next day in the US, very cheaply), and attached a couple of each side of the unit (both power cord and the cable going to the handpiece).? Switching the IEC receptacle on the unit with one that's filtered may be impossible, due to how diminutive this unit is (it's a "KSGER" that's about 5.5"x3.5"x1.5"). I'm very happy with how it works other than this dispersed EMI. There's no way this would pass a closer look by the FCC from a compliance?perspective.? I'll assess how well the ferrites are doing at suppressing?this stuff. Other than that, maybe one of those TRIPP-LITE units may be a choice, particularly?if I get a bargain somewhere.? ? It's okay. We're good here.
Thanks,
Ross
-----Original Message-----
From: [email protected]
<[email protected]> On Behalf Of Wilko Bulte
Sent: Friday, August 04, 2023 9:31 AM
To: [email protected]
Subject: Re: [Test Equipment Design & Construction] EMI filtering on power
cord
It is based on Pyvisa.
I personally use it with a Keysight USB-GPIB interface (would need to dive
under the equipment table for the partnr)
Wilko
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Re: EMI filtering on power cord
Further thanks to all that pitched in. As usual, a side conversation at least as interesting is?unfolding.?
On my side of things, I've grabbed a box of assisted?clamp-on ferrites from AMZ (can be had next day in the US, very cheaply), and attached a couple of each side of the unit (both power cord and the cable going to the handpiece).?
Switching the IEC receptacle on the unit with one that's filtered may be impossible, due to how diminutive this unit is (it's a "KSGER" that's about 5.5"x3.5"x1.5"). I'm very happy with how it works other than this dispersed EMI. There's no way this would pass a closer look by the FCC from a compliance?perspective.?
I'll assess how well the ferrites are doing at suppressing?this stuff. Other than that, maybe one of those TRIPP-LITE units may be a choice, particularly?if I get a bargain somewhere.?
Thank you, Radu.?
It's okay. We're good here.
Thanks,
Ross
-----Original Message-----
From: [email protected]
<[email protected]> On Behalf Of Wilko Bulte
Sent: Friday, August 04, 2023 9:31 AM
To: [email protected]
Subject: Re: [Test Equipment Design & Construction] EMI filtering on power
cord
It is based on Pyvisa.
I personally use it with a Keysight USB-GPIB interface (would need to dive
under the equipment table for the partnr)
Wilko
|
Re: EMI filtering on power cord
It's okay. We're good here.
Thanks,
Ross
toggle quoted message
Show quoted text
-----Original Message----- From: [email protected]< [email protected]> On Behalf Of Wilko Bulte Sent: Friday, August 04, 2023 9:31 AM To: [email protected]Subject: Re: [Test Equipment Design & Construction] EMI filtering on power cord It is based on Pyvisa. I personally use it with a Keysight USB-GPIB interface (would need to dive under the equipment table for the partnr) Wilko
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Re: EMI filtering on power cord
It is based on Pyvisa.
I personally use it with a Keysight USB-GPIB interface (would need to dive under the equipment table for the partnr)
Wilko
|
Daniel Ricardo Perez
