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    Forum server was down around 0100Z to 0200Z 07 February 2014

    Couldn't connect or ping the forum URL, but other related sites were up and running OK.
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    PWM for Transistor Switching

    Please send a diagram.
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    Some question about a circuit I have built?

    @Roskko57. Other than the fact that I seem to have a couple of wobbly diodes, I hope the idea seems clear. This hopefully represents the solenoid keyed by a pulse to gate of the MOSFET as normal. Concurrently a pwm pin is chopping at a several kHz the output of a GP NPN transistor, with the...
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    PICAXE is in Space

    Not from the International Space Station, but don't those two connectors look a bit like USB connectors, CoTS technology . . . Apple white?
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    Need help with "Motorized macro rail on the cheap" macrophotography project

    @Jon, not exactly a matrix board output, but close enough to be easily translated. I haven't put blobs on wire junctions and where crossings aren't conveniently under resistors I have put in the bridges, so it should all be fairly intuitive. The Picaxe end of things has been re-jigged and is...
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    Need help with "Motorized macro rail on the cheap" macrophotography project

    I have just come off the radio and read your last. I have just checked the correct download circuitry and it should be as follows: Output connector shown@ Pin 1 serial out (TX) Pin 2 serial in (RX) Pin 3 Ground On the original diagram we have an anomaly in that the serial out pin has a lead...
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    Some question about a circuit I have built?

    Here is some code, written but 'not yet checked'. Potential grey area is in the trigger checking, so hanging a LED on the end of the 1K resistor on pin C.4 to initially view what is happening and checking for correct operation, before connecting up the transistor and 12V circuit items. It may...
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    Infra Red Remote bit banging mischief maker

    Hello bit bangers, some strategic advice please, if you will. I have a LED020 IR sensor (from Tech Supplies) and have fed the output to a Logic analyser which seems to indicate that the framing from the family TV STB remote control has pulses that are either 0.9mS or 1.8mS in duration, with a...
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    PICAXE is in Space

    @Crowland, it will be tumbling, so you may experience some very fast fading, which is probably the least of the problems. With a rubber duck, don't forget that it is at it's most sensitive broadside onto the antenna, so don't point it in the general direction like you would a yagi. For this...
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    PICAXE is in Space

    Simulation Wednesday 25 December 2013 11.40 Notice that with TLE from 30 Nov 2013066W and 11 Dec Eagle 2, same Norad object, that by lunchtime on Christmas day there is a significant separation, which is a good indication that TLE should be kept up to date. Seven days is a good figure to aim...
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    PICAXE is in Space

    Currently the position appears to be that we are listening for $50SAT and tracking catalogue #39436, object 2013066W. it is for the satellite operators, Stewart and other project members, to eventually determine if this object is indeed their bird or not. For up to date TLE, readers can either...
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    FET driving

    This might help somewhat on the Rapid Electronics front. £10 before VAT spend only required for the next few days, so not as big a burden as having to spend £30 (£35) before VAT.
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    how do I add a switch to the input pins on the sd21

    Additional info: Traditionally the value used for pull up/down resistors is 10k. This is a value that will limit the current to 0.5mA should a normally closed switch be used when using a +5V supply. A normally open switch is more common as there is no residual current drain. A higher value...
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    Newb Question...

    Short answer - NO. Longer answer, I'm now running LTspice under Linux (WINE) and learning slowly, substituting links for the switches and running the simulation. it's CRAP - The simulation, not the program. I too had come to the conclusion that everyone was using SPDT switches and felt that it...
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    Newb Question...

    You merely need SPST momentary action push buttons for feeding an R2R ladder into the ADC input - as shown. The above has been shown to be flawed and is no longer recommended.
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    New to serial

    With communication from one master to a number of slaves, RS485 transceiver chips might be considered to allow reliable serial connection between a large number of PICAXE systems. In it's simplest form the transmit output from the master connects to DI and the DE and -RE pins held high with a...
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    Serial to RS485 problems

    I don't suppose that the PC can be configured to generate 2 stop bits? That would possibly be simpler than parsing the strings to send in a loop and sending them singly with a slight pause between. I too tend to think about automatic transmissions at full tilt and think that the generation of...
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    Can PICAXE outputs only be HIGH or LOW?

    What is a buffer in this context? What op amp? LM324 quad or a dual or a single single voltage rail. Pages 10 to 19 give you the standard applicaton circuits to save on the grey cells. Page 13 fig 11 is the voltage follower, or buffer circuit. A...
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    Linear scale on 20 x 4 oled

    Do you realise just how many chocolate bars it takes for a reliable manual adjustment mechanism to work properly? My, the AXE091 seems to be a bit of a Rolls Royce job. I get by with the AXE029 and because I use it with 08M/M2 chips, which it wasn't designed for as well as 18M2, I just waste...
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    I'm tempted - nice price - Rigol UK DS1052E scope I can hear Santa coming already . . . :cool: Anyone have any first hand experience?