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Hi Archie,
This is probably an overkill for your application but I have used the 16F1783 for precision PWM applications as it contains 2x 16 bit programmable switchmode controllers. (along with 12...

Hi,
A friend with a Prius had his car for 9 years and claimed he hadn't noticed any drop in performance. His understanding was that a replacement pack was around NZ$3000 or about US$1600 which if...

This is a truly fascinating thread and I'd like to thank Norm for the post that kicked it all off.
Electric vehicles hold a fascination for me too and I try to keep abreast of the developments. ...

Hi Tim,
Many thanks for the detailed explanation. Sounds like you will need a fairly fast amplifier and comparator to match the bandwidth your 'scope is probably offering but I'm sure they are...

Hi Tim,
This might be a bit simplistic but do you need to read/analyze every frame? Could you analyze frame 1, send data during frame 2, analyze frame 3, send data during frame 4....
I've followed...

Found it!
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Regards to all,
David

Hi John,
I think I've been using the site since about 2004 and I've changed my password before but I just can't see where to electively change a password. My temp password expires within 24 hours...

This is embarrassing - my password timed out and I have been allocated a new, temporary password but I can't see where to permanently change it.
I suspect this is an age thing.....

Best regards,...

Apologies - I've goofed. I had assumed these were current sensing Hall Effect devices but the original post mentions "position of the poles" so obviously they are magnetic sensors.
However - much...

Hi,
The zero current output voltage of Hall devices will vary from unit to unit so while they do give a typical output voltage (say 2.5V for 5V Vdd) they don't give the total variation you may have...

Hi,
I think minimum delta Vref for that device is specified as 2V. There are also constraints on the +ve and -ve Vref values as below.

Hi Harm,
All understood now. That IC may be a precision overkill for your application. For a start sine waves are not very exciting musically and usually something like a sawtooth wave (not...

Hi Harm,
That IC I referenced can output around 12MHz as its top frequency (approx half its clock rate) In real terms probably about 5-6MHz would be more realistic. The device has all the phase...

Hi Harm,
Isn't that 20 instruction per phase point?

Anyway - I found something in my stoneware archives which may be of interest to you. I'm never sure how functional some of my old experimental...

Hi Harm,
Is this part of an 8 bit sine look-up table and related to your previous question about maximum HBus speeds?
If you can spare an entire 8 bit port then it's hard to beat a simple 10pin, 8...

I still think the simplest approach is to take a COTS Bluetooth audio transmitter/receiver pair and slap decent high gain antennas on each end of the link.
Class 1 is 100mW or +20dBm so you would...

Hi John,
I would have to agree that 25dB gain seems a bit too optimistic but even if it provides 12dB it would be enough. The elements do seem a little chunky but I guess they are covering a fairly...

How about a Class 1 Bluetooth audio device (+20dBm) and high gain directional antennas at each end? The link budget should be more than enough and the link would be quite robust due to the narrow...

Thanks for posting - a most interesting read. I would have thought that $200 million was cheap for technology that might take you from current energy densities of around 240Wh/kg to 500Wh/kg. ...

Wow John - I only learned about 807's as a youngster, I never said I had used them myself. Did you know a guy called Moses at school?
When I was about 12 I made a really nice regenerative receiver...

Hi,
I remember my dad making a PA system for our new local primary school back in 1954. It had a microphone, turntable and Class A amplifier using a war surplus 807 valve.
The 807 was one of those...

Well I 've just found that by raising the modem antenna off the floor the phone calls are totally reliable. During the early part of the day the SMS texts were solid and reliable but phone calls...

Hi,
Just a quick update on migrating the alarm via a 2G modem. (SIM800L v2.2 EVB)
The modem arrived today and I found out that Vodafone are still operating 2G data and voice services here in NZ...

Thanks guys.
It was a fairly quick and dirty lash up and I hadn't been doing code for some time. I love the way you can target a single piece of data in a GPS sentence without recording a whole...

Hi,
The Beitian BN-880 uses the u-blox Neo M8N module and I agree it is an excellent performer.
I suspect other modules are using the Neo M8M which is very similar but ROM based (not Flash) so...

My apologies Bob - that timing figure is 10nS and I read it as 10mS. That's not too bad at all.
BTW - attached is a BS-880 (w/o compass) tracking indoors. GPS, Glonass, Galileo, SBAS, WAAS, QZSS. ...

Hi,
Yes Beidou is mainly Asia at the moment but is intended to be global next year and at the rate they're launching satellites I can believe it. Of course there may be military priorities as well....

Hi Bob,
When they say "supports DGPS" I think that means it accepts serial correction data from a DGPS receiver. Because conventional DGPS operates on a carrier around 300kHz the antennas tend to...

Hi Tim,
A few years back here in Auckland we had a company making thin frames to go on flat screen monitors and these had line scan cameras (similar to yours) that scanned X and Y over the entire...

Hi,
I'm trying to talk you out of PIDs and wheel speed sensing and initially focus on the basics of fwd/rev common throttle and left/right differential throttle. The rest can be added later if...

Hi Craig,
Thanks for the link. Looks similar to what we used to call an inverted F antenna which could be pressed metal or done in copper on the pcb. I think the stamped metal is more accurate and...

Hi,
Looking a the pick up pattern for that antenna it's very similar to a dielectric patch on a modest groundplane and it's also lower gain. It won't see much below its own horizon so if mounted on...

I have to say I'm impressed by someone writing their own 3 phase controller and then building the hardware too! Especially given these are sensored BLDC motors.
I have to ask - is it essential to...

Hi Craig,
Wow - that's a comprehensive reply and I'll use that as a reference for my project. I'm sure others will benefit from it also.
I'm familiar with u-center but was unaware of the other...

Many thanks for the reply.
I have a SIM800L module on order and will attempt to get SMS working on that. As you mention they are a trivial cost so if it's not suitable I can buy another as per your...

Hi,
That's an ambitious project you're in to there.
This sounds like the classic differential drive where forward/back on the joystick is common throttle with center off and left/right is...

Hi John,
Yes 2G has gone here and I believe 3G's days may be numbered but at least it will buy me some time.
I've not been very active for some time and somehow my details were no longer valid so I...

Thanks Tim,
That's a serious chip for capacitive sensing. Did you try a fixed capacitance in place of the probe to try to see where the instability was coming from?
As usual the theory is much...

Hi Tim,
Given that you're working with water and air you would think a dielectric sensing system would pick up the 80:1 ratio difference. May I ask why the capacitive sensing system didn't work for...

Hi George,
If you're only concerned about long term accuracy could you use the AC mains frequency to keep time? Digital clocks only ever need adjusting when there's a power cut and even this can be...

Hi John,
Thanks for the reply. I'm not really up with the play on the current cellular status. I know 2G has gone but I thought there was still a heap of 3G and 4G stuff around. I will see if I...

Hi All,
I need to migrate a monitored house alarm from the present copper line to GSM so we can eventually adopt a fiber system that the telcos are pushing.
When I say monitored it's only sending...

Hi All,
This is a simple project to allow the logging of RC plane speeds to help determine battery, motor and prop variables.
The code is crude and simple but has worked well to date.
Basically it...

Test

Declare Hserial_Baud=9600
Declare Hserial_SPBRG=25

End of test

Hi,
Well that last post was one extreme and really only intended to be used as a good, stand-alone reference rather than be used in some other project as a clock source.
You may want to check what...

Hi,
The ultimate DIY frequency source is probably a frequency locked loop (FLL) where the long term stability of a GPS timing signal is combined with the short term stability (phase jitter) of an...