modified 4 years ago

⏧Diode product mixer problem⏧

01:47:55

⏧Double sideband mixer⏧ 

It works when you fire it up, but... I cannot seem to get the carrier nulled out. It starts ok then progressively creeps back to a non nulled state.

Any positive help on this is appreciated. 

published 6 years ago

kiani

6 years ago

Fiddle factors plus shotkey diodes

kiani

6 years ago

http://everycircuit.com/circuit/5249811058786304

kiani

6 years ago

Just messing with your circuit.

zorgrian

6 years ago

@kiani, thanks but your version seems to be AM as you have put the pot to one end... AM would be expected. It should be possible to do this with just plain signal diodes. It is possible as other have done this but I cannot seem to get this right

zorgrian

6 years ago

I just set the two nulling Cs to 10p each. The problem must be the capacitance of the diodes or and the capacitance to ground currently set at 20nF. I guess these caps are 'slowly' charging up like a diode pump, which is why I put the two caps in at either end of the pot I can make the DSP last longer by lowering the signal level to just above 7dBm (0.5V) but this is a cheat as the same thing happens eventually

zorgrian

6 years ago

*DSB

lenzrulz

6 years ago

Check this out zorg: http://everycircuit.com/circuit/5430553727729664

kiani

6 years ago

Don't know anything enough about mixer circuits,, ii reducrd the diodes resistances to 300mOhms from 2 Ohms, and yhink there is imprivemrnt, i don't know what the resistance of signal dides are, guessed....

zorgrian

6 years ago

@kiani, thanks for looking at the problem. You are right to look at the impedance of the diodes, but this is a very complex situation, as when looked at one way they are very very low impedance and the other high. Diode mixers are simple, but getting them to work on EC is NOT

zorgrian

6 years ago

@lentilMentil, Your 555 waffle has nothing to do with reality here

kiani

6 years ago

@zorgrian what you say about the impedance of diodes being different from another path,, reminded me of Braess paradox..!! Also i find EC does not like mix of voltage sources and logic gates and analog components,,, hope you'll find an answer.

lenzrulz

6 years ago

Enjoy your reality @zorgpostnrun...😂

hurz

6 years ago

Pay very close attention to Lenny's comments and decide for yourselves if he is here for electronics or conflict.

kiani

6 years ago

Don't concern yourself s with Lenzul ha/she/it,, he hsd already admitted he/she/it is the idiot of the village. A very nasty idiot.

kiani

6 years ago

Csuse he is laughing..as if it id a laughing matter.

lenzrulz

6 years ago

Just returning the favour in full, not too pleasant when the proverbial shoe is on the other foot...😬

hurz

6 years ago

electronics or conflicts?

lenzrulz

6 years ago

You choose!

kiani

6 years ago

There had not bern much of elrctronics for the past 5 years from lenzul,,, while planty of conflicts,, he seem to be having a lot of fun,, laughingly...

hurz

6 years ago

thats his only fun on everycircuit he is here for, 1000% sure after observing him the last five years

kiani

6 years ago

Lenzuls existsnce on EC and everything he does is denigerating and condescension of all EC community members,, csuse he has chosen to be a charlatan on EC.

zorgrian

6 years ago

@lentilMind, what do you think might cure the double sideband mixer problems? No ideas? Oh! What a surprise!

zorgrian

6 years ago

@lenibeniNonceHead doesn't know what a side band is

zorgrian

6 years ago

Lentil is elected as president of the cretin club here

zorgrian

6 years ago

It (the lentil) is a dawk head, hypocrisy speaking fuck faced shit for brains, dullard

lenzrulz

6 years ago

Temper tantrums zorg? Too bad, learn to take responsibility for your bad behaviour, remember, you are the company you keep. If you choose to be a follower of someone socially inept, then learn to live with the scourge of fleas.

hurz

6 years ago

Lenny, you love conflicts, much much more then electronics

zorgrian

6 years ago

@lentil wtf? I don't need anecdotal contribution from you. You need to increase the thorazine drip. Better, go shoot yourself as the world's population stands at over 8 billion, all and any help we can get with population control is admirable. In the absence of guns, you may choose to allow hungry crocodiles to eat you.

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