Why do you need a capacitor that large?Hayrettin Demir said:Firstly , Error Relay Coil parallel appr. 4700uF Condensator required.
What is the resistance of the relay coil?
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Why do you need a capacitor that large?Hayrettin Demir said:Firstly , Error Relay Coil parallel appr. 4700uF Condensator required.
ljcox said:Why do you need a capacitor that large?
What is the resistance of the relay coil?
ljcox said:The first "computer" - the Colossos - was built in England during WW2 to assist in decoding German cyphers was partly electronic and partly relay logic.
Nigel Goodwin said:And was then dismantled and the parts returned to the Post Office - an amazing story!.
Britain had a massive world lead in computers and all from a single guy who worked for the Post Office, and 'stole' all the parts to build it!
I'm sure I read somewhere a bit back that they have built a reconstruction of it now?.
X4 is operated for the time that the B4 button is pressed, so I don't see why you need to increase its release delay.Hayrettin Demir said:Ok...
Now identically for X4 Relays delay time required.(approx. 1-3sn)...
The reconstruction was driven by Tony Sale. Some years ago I looked at their web site and obtained some circuits on a CD that Tony sent to me (there was a modest cost).ericgibbs said:hi Nigel,
He [Tommy Flowers] actually spent a £1000 of his own money as well as the 'borrowed' bits to build the first one,
which after many years the Govt paid him back..
The other 9 Collososii were built with Govt funding.
Mr W Churchill at the end of the war ordered all the 10 to be dismantled and the documentation to be destroyed..
he was concerned it would fall into the hands of the USSR.
The working reconstruction was shown working on a recent TV program...
ljcox said:X4 is operated for the time that the B4 button is pressed, so I don't see why you need to increase its release delay.
Hayrettin Demir said:If B4 button 0,1sn pressed...
Then X4 0,1sn operated and DS 0,1sn active.
(DS --> 1-3sn active to be). So you want to limit the time that DS is energised regardless of how long B4 is pressed. If so, then you will need to do more than just making X4 slow to release....
So ;
If B4 button 10sn or more pressed...
Then X4 10sn or more operated and DS 10sn or more active...
This is a problem for DS...(DS is break down !). Yes, DS is likely to over heat and burn....
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Series resistor (82 Ohm) is only for charge required. Yes, but it makes little difference to the release time. As I said previously, this is a standard technique used to increase relay release time.
I have never seen a diode across the resistor.
What you are missing is that the resistor increases the time constant and may in fact sligthy increase the release time compared to the case where the diode is included.
It is a complex situation. The initial voltage across the coil will be 12 Volt, not 11.3 as you have shown since, due to the coil inductance, the current does not change when the button is released.
In your second diagram, ie. where there is no diode, the voltage across the coil will be 12 Volt and the voltage across the resistor will be I * R where I is the coil current and R is the resistance of the resistor. For example, if the coil resistance is 600 Ohm, the current will be 12/0.6 = 20 mA.
If R = 82 Ohm, the voltage across it will be 20/1000 * 82 = 1.64 volt.
You have added the capacitor and resistor voltages.Hayrettin Demir said:Please check again...