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May 14, 2020 19:24:50 GMT
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Phil, this may be a goofy question, but what would it cost to put A/C in that car? Are there any reasonably priced kits? John Couple thousand, at a guess. Vintage Air do a universal kit. My problem is finding space for the compressor, and there's space only for a regular Vee belt. Phil
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May 14, 2020 19:30:43 GMT
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Cleaned the workbench and put my radio back on it after a year and a bit of it sitting collecting dust. Fixed the schematic to represent the new power supply. Gotta get back to this now.
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May 14, 2020 19:31:42 GMT
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Phil, this may be a goofy question, but what would it cost to put A/C in that car? Are there any reasonably priced kits? John Couple thousand, at a guess. Vintage Air do a universal kit. My problem is finding space for the compressor, and there's space only for a regular Vee belt. Phil Personally I would rather wind the window down - let the breeze flow in and listen to that lovely 8 track pot motor
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May 14, 2020 20:15:09 GMT
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There's a lot of telephone diallers in that wiring diagram
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Frankenhealey
Club Retro Rides Member
And I looked, and behold, a pale horse! And its rider's name was Death
Posts: 3,875
Club RR Member Number: 15
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1951 Pontiac ChieftainFrankenhealey
@frankenhealey
Club Retro Rides Member 15
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May 14, 2020 21:32:19 GMT
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My problem is finding space for the compressor, and there's space only for a regular Vee belt. Problem solved
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Tales of the Volcano Lair hereFrankenBug - Vulcan Power hereThe Frankenhealey here
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Personally I would rather wind the window down - let the breeze flow in and listen to that lovely 8 track pot motor Anywhere else, I would agree. The breeze doesn't cool you in high summer here. The sun beats down on the roof making the cabin hot, the air outside is 35+ degrees C and very often at or above the dew point meaning that any perspiration doesn't actually evaporate with a breeze because the air is already saturated. On days like those, aircon is really the only comfortable way to drive. It's not as hot as some places. People scoff that they've been to Death Valley in August and the air is warmer than your body. Very true and that's damn hot but it's also incredibly dry air and you still stand a mild chance in the shade of regulating your body temperature for a short while. Humid heat is killer at lower temperatures. I'll be driving it mostly in wintertime... Phil
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Last Edit: May 15, 2020 3:36:41 GMT by PhilA
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There's a lot of telephone diallers in that wiring diagram The part I'm most interested in is contained within the 4 on the right hand side, starting with "DET. 6SQ7 AUD.", as half of that tube is audio pre-amplification. That then feeds into the power amplifier which is a full linear complimentary push-pull design. Uh yeah, if you say so. Well, figure this. The telephone dial pieces can only push power out. In the left hand side all you are doing is pushing electrons around and they're pretty small and easy to move so they bounce around as they are pushed by the circuit. However, the final output is the loudspeaker. That will move if you give it a shove but takes a finite time to stop moving, like anything with mass, it has momentum and inertia characteristics plus a really high coefficient of drag (it's designed to move the air, not slice through it, remember). So, a hard push is really effective at making it move one way, but let go and the cone has to return back by the springiness of its suspension. This method works but not once you begin to turn the volume up a bit. So, the phase inverter (PH. 6SQ7 INV.) is employed to turn the signal upside-down and fed into the bottom telephone dial 6V6. Doing this means that when the voltage is climbing, the top 6V6 pushes the cone and the bottom one does nothing, but when the voltage falls the top one goes into freefall but the bottom one pushes the other way, dragging the loudspeaker cone down forcefully. Complimentary class AB1 Push-Pull. It just sounds better that way. Phil
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A practical thought experiment on the circuit above.
Imagine you have one of those Chinese paper fans. Mount it on a hinged stick so it can move up and down (with the fan horizontal). That represents the loudspeaker cone. It will come to rest at the bottom because a small spring gently holds it down and limits its motion somewhat to a maximum stretch and minimum squash.
Install an air nozzle below, pointing at the fan. You control a small movement of a valve that opens and restricts air flow. The more you open the valve, the more the fan is blown upwards.
That's the top 6V6 tube. If you open and close the valve slowly the fan position will mimick that of the valve. Now, move the valve quickly from minimum to maximum and back again and again. The fan gets blown to the top, you turn the air off but it is still moving up; turn it in again and it's not had chance to move back under the spring, it has too much momentum. You're now saturating the amplifier.
So, install a second nozzle above, that points downward at the fan. Add a second valve that is open when the first is closed and vice versa.
Now, at the bottom, the lower nozzle doesn't blow but the top one does, maximum, holding it all the way down. As you dial the valves there's always some push from each nozzle, holding the fan in balance.
Now move the valve rapidly. The fan is pushed and pulled and follows your motion much more effectively. That's class A push-pull.
Now figure you can push further if you make a bit of overlap to the valves- that is one closes before the other is fully open. You give yourself better range and more ability to push. That bias is class B; add the two together and you get AB1. The best mix of power output versus quality for the money. Class A is technically the best but it's very wasteful and you don't get much audio power output from it. AB1 is a trade-off which works exceptionally well.
This is also why they're called valves in the UK, because the power beam to the plate is synonymous to a valve bring opened and closed like in the example above. America went with a more physical description, they're made from glass tube.
Phil
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Last Edit: May 15, 2020 4:52:27 GMT by PhilA
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fascinating, thanks phil, reminds of when i was trying to get my sun 745 oscilloscope to work .(with no knowledge what so ever)
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May 15, 2020 22:41:01 GMT
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Here we go. This is what I'm building. Correct pinouts, modified power supply. New component parts ordered. 12V tubes ordered. Watch this space
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May 17, 2020 21:26:27 GMT
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Got my workbench all set up properly. Ready to go! Phil
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May 17, 2020 21:44:21 GMT
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Way beyond my comprehension. John
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Way beyond my comprehension. John No need for it to be. There are the following things: Door: (1976) A useful portal to outside. Keeps the wasps outside (mostly). Lamp: (1982) Handy, though this one smells bad and if plugged in backwards, the switch becomes live. Tools: (Various) AA tweezers, small screwdrivers, magnet-on-a-stick, wire cutters, pliers etc. Solder (60/40): (1996) Proper rosin-core 60/40 that you don't feed to the children. Not RoHS approved. Bin: (2018) Handy place to put bits that don't belong inside the thing being worked on. Radio: (1951) What's being worked on. 12V DC PSU: (1998) A 3 Amp DC power supply, regulated. Iron: (1973) 25W Weller fine-tip. Solder sucker: (1999) A damn good Solda-Pullt. Outlets: (2016) Contains 120VAC at 60Hz, 15A. Flashlight: (2018) A Nebo "Big Larry" COB LED flashlight that is handy for illuminating dropped screws and stuff. VTVM: (1958) Heathkit V7-A Vacuum Tube Volt Meter. A "Chinese walls" type meter. Very accurate. Can be used to measure the resistance of lesser meters. Logic Analyzer: (1985) HP 1631D. Useful for finding faults in digital electronic circuits. Also has a handy twin-channel storage oscilloscope. Waveform Generator: (1974) WaveTek 159. You might know the name of the company that bought them- Fluke. this creates sine, square, sawtooth and triangle signals at arbitrary frequencies. It was not very accurate and still needs work but it good enough for now. Electronic Counter: (1964) HP 5245L. Good up to about 3MHz, this will count, give time period average, jitter and frequency measurements. DVM: (1977) Systron-Donner 7004A. High precision digital voltmeter. Good down to 0.0001 Volt, which is really handy for setting stuff accurately. Universal Counter: (1977) HP 5315A. 100MHz counter. Twin input, can provide all kinds of useful measurements. Nicely accurate. AM RF Generator: (1946) Taylor "Windsor" 65B. 100kHz to 27MHz AM RF generator. Has AM oscillator to modulate a tone onto the signal. All pretty simple stuff, all useful for one thing or another --Phil
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Last Edit: May 18, 2020 0:59:21 GMT by PhilA
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eurogranada
Europe
To tinker or not to tinker, that is the question...
Posts: 2,496
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Say what?
Well as long as you know what to do with all the stuff, right?!
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you lost me at door ..oh i have one of those other things, in my ghetto test area/dining room table.. found this down the scrappy .. and amazingly it worked .i used it to see if a toothed wheel on my kenwood chef would work as a signal generator . as you were
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glenanderson
Club Retro Rides Member
Posts: 4,121
Club RR Member Number: 64
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1951 Pontiac Chieftainglenanderson
@glenanderson
Club Retro Rides Member 64
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I have a lamp.
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My worst worry about dying is my wife selling my stuff for what I told her it cost...
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And I've got a an old bulb that might / might not fit the lamp
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Duggy
Part of things
Posts: 129
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May 18, 2020 10:36:01 GMT
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I have a multimeter that I struggle to use for anything other than continuity. Maybe I should have listened more in Physics at school instead of daydreaming about bikes, birds and football! Keep it up, this is one of my favourite threads on here.
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Last Edit: May 18, 2020 10:36:50 GMT by Duggy
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May 18, 2020 12:41:13 GMT
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Say what? Well as long as you know what to do with all the stuff, right?! Unfortunately, yes.
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May 18, 2020 14:24:27 GMT
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found this down the scrappy .. and amazingly it worked .i used it to see if a toothed wheel on my kenwood chef would work as a signal generator . That does the same things as my HP Universal Counter- it's a really handy thing to have. those little portable ones are surprisingly accurate, even after all these years. This HP one has a synthesized timing circuit that hasn't drifted or gone bad- looks like yours is still behaving, too. --Phil
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