Hartley or Colpitts oscillator

I need Hartley oscillator or Colpitts oscillator. I tried a lot but failed. I am simulating circuits on multisim but not been able to get sine wave. Can anybody help me with that??
I am using these oscillators because I want high power oscillator in high frequency range.

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Why don’t you make a low power oscillator and amplify the signal with an AB 500 watt amplifier.
m_uamir72001 (author)  Josehf Murchison3 years ago
Dear, I there is a link of data sheet of a transistor and its Typical frequency is 30MHz. What is meant by "typical frequency"??

2nd this is about op amps. I need a analogue devices op amp. which part you will suggest??
Typical frequency in this case is the harmonic oscillator like in this flyback circuit.

As for op amps:

MCP601 1 op amp MCP606, TL091

MCP602 2 op amp MCP607, TL092

MCP604 4 op amp MCP609, TL094

LMxxx series

108-208-308 1 op amp IC

158-258-358 2 op amp IC

124-224-324 4 op amp IC
Flyback 1a.gif
m_uamir72001 (author)  Josehf Murchison3 years ago
That's What i am doing it now.
Just Google

Crystal oscillator circuit

Sine wave oscillator circuit

Crystal sine wave oscillator circuit

You will get thousands of basic oscillator designs you will need to tweak.

Then Google

Power amplifier circuit

AB amplifier circuit

500 watt ab amplifier circuit

You will get thousands of circuits from 1 watt to over 5000 watts from 6 volts to 600 volts.
m_uamir72001 (author)  Josehf Murchison3 years ago
Yes, I already have a power amplifier circuit and it is pretty good I just need NPN and PNP transistor with HIGH POWER AND HIGH SPEED.

I hope you could help me with that.
These are complementary transistors.
2SA1943 and 2SC5200 230 Volts 15 Amp 150 Watt 30 MHz
m_uamir72001 (author)  Josehf Murchison3 years ago
It worked thanks.
How much maximum frequency and maximum power we can get from an amplifier. I mean what is the latest technology about amplifier.
Public ICs or private ICs the biggest problem is everything is not public then the manufactures use alphanumeric reference and not properties based references. When I look for a transistor in a data book of transistors I get 2N3904.when I look in my filing system I see watts, then volts, then hurts, then complementary. Manufactures don’t do that so you ether know where to look or you are screwed, the transistors I referenced you I have in my stock of parts so I only looked in my filing system, watts, volts, hurts, complementary, not alphanumeric.
m_uamir72001 (author)  Josehf Murchison3 years ago
Suppose I found a transistor with 100W power, What does it mean? how much amperes it can handle.
Watts is amps times volts so 100 watts means a transistor like 2SC1114 operates between 4 amps 25 volts and .33 amp 300 volts Max. However the transistor won’t handle 300 volts and 4 amps that is 1200 watts the transistor will blow and quite impressively.

If you look in a data book on transistors it will have a list of properties like this transistor.

Absolute maximum ratings (Ta=25℃)
SYMBOL           PARAMETER                      CONDITIONS       VALUE      UNIT
VCBO                 Collector-base voltage         Open emitter           325            V
VCEO               Collector-emitter voltage         Open base             300            V
VEBO                   Emitter-base voltage           Open collector          7              V
IC                               Collector current                                             4              A
PC                  Collector power dissipation          TC=25℃             100            W
Tj                          Junction temperature                                         150            ℃
Tstg                       Storage temperature                 -65                  ~150          ℃

These are maximum ratings but you can’t use all the maximums only watts and ether volts or watts and amps or somewhere in between on the two.

You can get free pdf data sheets on semiconductors at these two web sites, just enter the part number in the search box.



Some transistors have only numbers on the face like D1169 the part number is 2SD1169 or C1114 is 2SC1114.

Keep these two sights in your brouser favorites they are handy.
m_uamir72001 (author)  Josehf Murchison3 years ago
OOOhhhh... I get it now. Thank you so much.
Can I get your facebook or email ID ???
I would say just google me but 65,000,000 pages are a pain to sort through.
m_uamir72001 (author)  Josehf Murchison3 years ago
I sent you facebook friend request. I hope you don't mind.
m_uamir72001 (author)  Josehf Murchison3 years ago
Thanks again. It really helped me a lot.
m_uamir72001 (author)  Josehf Murchison3 years ago
Can you please tell me exact sine wave amplifier. That convert 25V to 220V and work on at least 7MHz
Orngrimm3 years ago
So 50MHz and what power do we speak of? 1W? 10W 1kW?
m_uamir72001 (author)  Orngrimm3 years ago
minimum 500W
Are you serious??? I mean: If you really want to deal with this kind of power you HAVE to know your ways around HF-Techniques and the dangers of that. 500W of HF is no joke and if you cannot even create a self-stabilizing colpits, i am sure you would KILL yourself and set the house on fire with a constraption you would have made.
See it the other way: If you dont know the basics and arent able to make a working colpits (Selfstabilizing), be GLAD you failed where and not after you bought 2000$+ worth of HF- & High-Power Transistors to boost the signal.

But if you want to ignore all thze precautions and walk unknowingly in despair: be my guest:
Since you want to deal with serious power, buying a decent functiongenerator is the cheapest part of your setup. Buy a selfmade if you want like http://www.ebay.de/itm/0-50Mhz-1Hz-Step-Dual-Channel-Sine-Wave-DDS-Signal-Generator-English-Software-/230799516483?pt=LH_DefaultDomain_0&hash=item35bcb92343 or buy a good laboratory-equipment.
Now you amplify the sine with some matching Transistors like a BLF369 for a price of over 400$ a piece. And without proper LAyout and Casing you will have a nightmare of ringing and distorting signals i promise you...
m_uamir72001 (author)  Orngrimm3 years ago
Dear! I am an engineer. I don't care that I fail because it makes me learn new techniques. I don't care that it is dangerous or not because i want to make it. I could also buy it from internet but i want to make it myself.I don't think that it is dangerous because it is just 500W (0.5kW).

There are two types of oscillators that i found on internet.
1: high power with low frequency
2: low power with high frequency

But I want High power with high frequency. transistor base oscillators are low frequency because of switching speed of transistors.

Hartley or Colpitts oscillator are those which can give me both (High power with high frequency) But make them stable is itself a difficult job.
That's why I need your help.
"transistor base oscillators are low frequency because of switching speed of transistors"
Oh.. Is that so? If you think so, you really should reconsider your degree in engineering...
What do you think is inside an Amplifier for those frequencies?? Magic smoke? No. It is a transistor-based amplifier.
If you would have checked on the Transistor i named (BLF369) you would see that this one is capable of up to 100MHz @ 500W.
Of course you have to make to complete circuit around it which i doupt will end in success since it seems like a lot of missing basics in electrotechnics...
Sorry pal, but dealing with this amount of power (Output) and heat (i think at least 200W) needs some considerations... Also your Powersupply will be a whole other story... For you are going for a cheap 1kW PC-Powersupply: Forget it.

And whats the fuss about the sinewave-generator anyway?? If you arent able to implement some real basics you will fail miserably the next step when it comes to designing the amplifier.

And NO:
There is no oscillator which will deliver 500W direct output. You HAVE to make your base signal first and then amplify it.

For sine-wave i always used quadrature oscillators and they never failed me if done right. But 50MHz is maybe a bit high for those standard OpAmps... You could use a LT6205 or similar (http://www.linear.com/product/LT6205) and make a quadrature-osc from those...

Also what purity of the sine do you need? If a purity of 2^10bit ADC is enough, you should go for a AD9850 or similar...

Also you can consider amplifying a really pure sinewave from a quarz. They are available in 50MHz and the only thing you have to do is design a pickup-circuit (Impedance-changer) and an amplifier-circuit.
+1 RF's nasty stuff, even for the initiated.
Thank you! At least someone here sees it...
+1 to you for your valiant attempt to instruct the "uninstructable". Seems that he cannot see the basics for his "degree"

Base signal first, then amplify it. I agree.
Wouldn't THAT be a superpower !
Even for the well-experienced
m_uamir72001 (author)  Orngrimm3 years ago
minimum 500W
padevries3 years ago
Why not use a lower powered oscillator and use some opamps to increase the power available... what frequency / power are you looking for?
m_uamir72001 (author)  padevries3 years ago
The IC base opamps are for low power. they can increase voltages but not power. other amplifier (audio amps) are for low frequency like 20k Hz. But I need 50M Hz
m_uamir72001 (author) 3 years ago
If I write "colpitts oscillator" on google it gives me thousands of circuits but non of them works. not even close to sine wave.