help me please in my voltage controlled oscillator design - Page 2 - Electronic Circuits Projects Diagrams Free

bere · 25th February 2005, 08:43 AM

thanx a lot for the detail.connecting to the breadboard wont give any problems,i hope.and hope that its not too large a circuit for the board i have,will tell you about the results.how do i show the output on an oscilloscope now?i just want to see if it produces oscillations,and that its sinusoidal?

bere · 25th February 2005, 08:43 AM

thanx a lot for the detail.connecting to the breadboard wont give any problems,i hope.and hope that its not too large a circuit for the board i have,will tell you about the results.how do i show the output on an oscilloscope now?i just want to see if it produces oscillations,and that its sinusoidal?

**Nigel Goodwin** · 25th February 2005, 09:07 AM

You shouldn't attempt to build RF circuits on breadboard, it's the worst possible method you could try to use. It's very likely the breadboard will prevent the circuit working, particularly at 60MHz.

The output of the oscillator WILL be a sinewave, the ringing action of the tuned circuit guarantees it - massively overdriving it 'might' possibly manage a squarewave?, but it's unlikely.

FRIED · 25th February 2005, 01:10 PM

Quote:

You don't want to be trying to build RF designs on breadboard, certainly not at 60MHz!.

I agree

Roff · 25th February 2005, 04:45 PM

Back in the days before Protoboards (which I think are what you are referring to as breadboards), I used to "breadboard" high frequency circuits on single-sided copper clad. I laid out the circuit on 0.1" grid vellum, drilled all necessary holes, then cut pads with an annular cutter called a Roto-Bor. Later I used Vector pad cutters, which you could (and probably still can) buy with or without a handle. The one without the handle worked well in a drill press if you had one that would run at low speed. It had a tendency to occasionally pull the pad off the board. I see that they are now charging over $60 US for them. What a ripoff!
I have bought (at Fry's) double-sided material with plated-through holes on a 0.1" grid, with ground plane on one side. A couple years ago it was about $120 for about 1 sq ft, but you can cut it up and make a lot of little circuits, so I think it's worth it.

bere · 7th March 2005, 06:16 AM

would you kindly help me in identifying some components i want to use for my phase locked loop.i want a phase comparator,a crystal and frequency divider.what are the different types that are there?

atferrari · 7th March 2005, 10:15 AM

but perhaps several of them...

Why not using perfboard? With little planning you can go away reasonably well, I think.

Agustín Tomás

bere · 8th March 2005, 08:06 AM

hie.i have got almost all the components now but could you help me with part numbers for commonly found phase comparators and frequency dividers.i have a 10mhz crystal,that means i need a divide by 6.

bere · 9th March 2005, 09:58 AM

how can you change a colpitts to act as a vco?where would you incorporate a varactor diode?

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25th February 2005, 08:43 AM	(permalink)
bere	reply to vco design thanx a lot for the detail.connecting to the breadboard wont give any problems,i hope.and hope that its not too large a circuit for the board i have,will tell you about the results.how do i show the output on an oscilloscope now?i just want to see if it produces oscillations,and that its sinusoidal?

25th February 2005, 09:07 AM	(permalink)
Nigel Goodwin	You shouldn't attempt to build RF circuits on breadboard, it's the worst possible method you could try to use. It's very likely the breadboard will prevent the circuit working, particularly at 60MHz. The output of the oscillator WILL be a sinewave, the ringing action of the tuned circuit guarantees it - massively overdriving it 'might' possibly manage a squarewave?, but it's unlikely. __________________ PIC programmer software, and PIC Tutorials at: http://www.winpicprog.co.uk

25th February 2005, 04:45 PM	(permalink)
Roff	Back in the days before Protoboards (which I think are what you are referring to as breadboards), I used to "breadboard" high frequency circuits on single-sided copper clad. I laid out the circuit on 0.1" grid vellum, drilled all necessary holes, then cut pads with an annular cutter called a Roto-Bor. Later I used Vector pad cutters, which you could (and probably still can) buy with or without a handle. The one without the handle worked well in a drill press if you had one that would run at low speed. It had a tendency to occasionally pull the pad off the board. I see that they are now charging over $60 US for them. What a ripoff! I have bought (at Fry's) double-sided material with plated-through holes on a 0.1" grid, with ground plane on one side. A couple years ago it was about $120 for about 1 sq ft, but you can cut it up and make a lot of little circuits, so I think it's worth it.

7th March 2005, 06:16 AM	(permalink)
bere	reply to my vco design would you kindly help me in identifying some components i want to use for my phase locked loop.i want a phase comparator,a crystal and frequency divider.what are the different types that are there?

7th March 2005, 10:15 AM	(permalink)
atferrari	A problem no... but perhaps several of them... Why not using perfboard? With little planning you can go away reasonably well, I think. Agustín Tomás

8th March 2005, 08:06 AM	(permalink)
bere	reply to vco design hie.i have got almost all the components now but could you help me with part numbers for commonly found phase comparators and frequency dividers.i have a 10mhz crystal,that means i need a divide by 6.

9th March 2005, 09:58 AM	(permalink)
bere	help how can you change a colpitts to act as a vco?where would you incorporate a varactor diode?