1000 Threads found on edaboard.com: Hf Oscillator
Hello I have many IF-transformers (cans) taken out from transistor radios and CB but I do not know their resonating frequency.
I have access to a spectrum analyzer so I would like to make an HF oscillator to find their frequency.
I have tried different oscillators from the internet but I could not make anyone oscillate.
I do not want a crysta
RF, Microwave, Antennas and Optics :: 11-22-2009 06:18 :: neazoi :: Replies: 3 :: Views: 1332
It depends on the rate of charge you plan. Considering 0.1C (1/10 th of battery rated amperage), ie, 10A, you need a power supply capable of supplying 13.5V 10A. This is 135W of output power. You could use flyback or forward here, although at this power, you should look towards half-bridge or two-switch forward.
For half-bridge, you need a
Power Electronics :: 07-13-2010 06:53 :: Tahmid :: Replies: 2 :: Views: 3643
I am trying to electronically alter the capacitance in a specific point in an analogue circuit, for example an HF oscillator. A varicap is not the solution I look for.
A switched capacitance bank could be one solution, but multi switch relays are needed
Electronic Elementary Questions :: 01-12-2012 06:34 :: neazoi :: Replies: 8 :: Views: 1299
I've build this oscillator and it works perfect but I need to switch the positions of the 2 variables capacitors to have the 15p-280p grounded (I have some Hf signals coming from antenna) The problem is when I permute the two CVs, I dont have the same frequency range ?? What can I do without changing the circuit? Thanks
RF, Microwave, Antennas and Optics :: 05-27-2007 09:35 :: falcone :: Replies: 3 :: Views: 1899
Thanks at first.If i want to let it oscillate in 500KHz(LF) or 900MHz(HF),How can i caculate,and any formula to evaluate the Zin for negtive impedence and C1,C2?My E-Mail:John_li3000@sohu.com,look forwards to your reply.
Analog Circuit Design :: 01-28-2008 02:08 :: John_li :: Replies: 13 :: Views: 2405
Hello I am building a QRP (CW) transmitter tor the HF bands 160m to 10m and I need an amplifier to drive my oscillator so I can get 1-2W max out.
I have found this circuit (picture at the bottom) and I have built the oscillator but I need to eliminate the interstage transformer (capacitive coupling)
I have managed t
RF, Microwave, Antennas and Optics :: 12-27-2009 13:51 :: neazoi :: Replies: 4 :: Views: 2360
I have built a hf start module for a tig welder, its basically a high voltage radio frequency spark gap oscillator driven by a car ignition coil, its aim is to start the arc from the electrode to the work esp on low welding voltages.
It works well on my dc output alternator generator welder, however I tried this device on a ac stick w
Hobby Circuits and Small Projects Problems :: 03-15-2010 03:44 :: dr pepper :: Replies: 1 :: Views: 4355
+/-5V on 50 Ohm means a +/-100mA delivering capability, are you ready for some complexer output stage to build? I think on "Composite amplifier" some discretes & HF Op + DC compensating low speed precision Op...
Your spec of less as 5ns for both edges isnt so full trivial (peak to peak 10V & 3dB bandwith of min. 70 MHz, even if your fre
Hobby Circuits and Small Projects Problems :: 07-16-2010 13:36 :: karesz :: Replies: 13 :: Views: 1809
Hi every one,
I do not know if I am in right topic section. I need some schematic circuit diagram of an HF Plastic welding machine (for creating Photo Albums). I want to assemble one for me by using FU 501 triode as the main oscillator/output tube.
Service Manuals, Requests, Repair Tips :: 01-24-2012 13:34 :: Saba Khan :: Replies: 0 :: Views: 932
Hello I alter the frequency of an HF (1-30MHz) crystal oscillator using an MV209 varicap.
I need to replace it with a greater capacitance range varicap to increase the tuning range, as much as the crystal permits it. Which one should I use?
1) 9.5v maximum tuning voltage
2) junction operating temperature more than 80C, since it
Analog Circuit Design :: 02-14-2012 19:17 :: neazoi :: Replies: 0 :: Views: 396
As vimalkhanna says, what frequency, power, supply voltage, etc?
Building a real class C oscillator can be very difficult to almost impossible. Real class C (with conduction angle < 120 degrees) is sensitive to envelope instability.
Because of the harmonic-rich content of the current waveform, getting the correct termination for the harmo
Analog Circuit Design :: 02-26-2012 12:33 :: WimRFP :: Replies: 12 :: Views: 1680
can any one help me to find 27 MHz with crystal oscillator Experienced and trusted...
Go and find an old 27 MHz crystal controlled CB radio, there are sources of CB radio circuit diagrams on the net
do some googling :) most of the circuits used a colpitts oscillator
what is the di
RF, Microwave, Antennas and Optics :: 03-07-2012 18:46 :: davenn :: Replies: 5 :: Views: 829
Yes; Google "oscillations and regenerative amplification using negative resistance devices" and you will find a good paper that includes a -R audio oscillator.
And here is a practical application of the principle at HF;
RF, Microwave, Antennas and Optics :: 04-09-2012 02:15 :: krp :: Replies: 1 :: Views: 638
The above links show how to design an oscillator for a certain configuration, but I was unable to see an example of how this theory can apply to the design on a practical circuit such as a colptts or a hartley oscillator.
Does anyone know where I
RF, Microwave, Antennas and Optics :: 05-08-2012 05:49 :: obrien135 :: Replies: 10 :: Views: 1106
can you explain more about RFC?
RFC derived from Radio Frequency choke . it will be open circuit instead of our desired frequency . it will use to prevent from unwanted interferences between our sources .
and how to check oscillator, if it's good condition ?
Do you have access to an oscilloscop
Hobby Circuits and Small Projects Problems :: 07-01-2012 12:00 :: goldsmith :: Replies: 6 :: Views: 1885
Hello I am trying to make a simple RTTY oscillator for the HF bands that can accept 1.2KHz and 2.2KHz audio tones.
Can this be done using a quartz crystal for better stability, or the crystal does not allow so much deviation?
Also are there any sources of such a schematic?
RF, Microwave, Antennas and Optics :: 06-29-2012 06:00 :: neazoi :: Replies: 0 :: Views: 189
If this is a normal crystal then this will specify a capacitive load for typical operation.
The problem will be that circuit layout is unknown and produces a significant capacitance.
The two capacitors for HF work are often around 10pF, hence the layout issue.
Keep the crystal leads close to the component pins, track the capacitors close to the
Embedded Systems and Real-Time OS :: 09-11-2013 16:00 :: pinout :: Replies: 1 :: Views: 390
Hello, which types of capacitors are best suited for an HF bandpass filter for RX only?
1. A Silver mica
2. An NP0 disk
RF, Microwave, Antennas and Optics :: 02-09-2014 14:31 :: neazoi :: Replies: 2 :: Views: 330
Anyone got any stuff on oscillator theory/design, in particular LC/crystal oscillators?
Professional Hardware and Electronics Design :: 12-03-2001 20:31 :: arebee :: Replies: 5 :: Views: 1586
I want to demonstrate a coupled oscillator circuit at graduate level. Can any one suggest some thing?
Professional Hardware and Electronics Design :: 12-07-2001 05:59 :: billano786 :: Replies: 1 :: Views: 1937
Who can give me a circuit netlist of 32768 Crystal oscillator for spice simulation!
My circuit cann't get up!
Other Design :: 01-01-2002 05:18 :: elone :: Replies: 8 :: Views: 14235
This post is long, so bare with me. I am attempting to design an FM receiver from scratch. My question, described below, is regarding practicle limits of quality factors. How do i chose components such that the local oscillator resonates at a specific frequency AND is stable..
Here is the calculation thought process, feel free to point out any
RF, Microwave, Antennas and Optics :: 02-03-2002 17:40 :: Mr.Cool :: Replies: 5 :: Views: 3134
I would like to ask what is the difference between crystall and crystall oscillator.
and also what is the difference between 2 pins crsytal oscillator and 4 pins crystal oscillator?
Thnx very much
Professional Hardware and Electronics Design :: 02-07-2002 00:22 :: Sunny :: Replies: 4 :: Views: 1273
Hi everybody !
I need an oscillator which runs at 32,83 MHz with +7dBm output power.
I want to keep it as simple as possible, so I want to use a crystal
oscillator and an op-amp.
As this design will be unique (no series production), I searched
some catalogues and found some off-the-shelf crystal oscillators
with 32 MHz and 33,33 (...)
RF, Microwave, Antennas and Optics :: 02-20-2002 08:59 :: feedbackkiller :: Replies: 6 :: Views: 3028
does anybody know something about YIG oscillator/filter recycling ??
There are often units (new and used) offered on the surplus market but they are almost all undocumented (custom). Any e-paper on the argument will be very useful and appreciated.
Thanks all in advance !!
Professional Hardware and Electronics Design :: 03-17-2002 14:51 :: syzzler :: Replies: 0 :: Views: 865
In my new project i may need a low phase noise 160 or 180MHz oscillator for AD9856 ( DDS chip). Someone suggest me to use a 10MHz OCXO to catch lower phase in near-band, in this project the phase noise of DDS output must below -70dBc @10Hz. If i use 10MHz ocxo, then i must use on-chip multipler inside AD9856, it cause some degrade of phase noise
Professional Hardware and Electronics Design :: 07-03-2002 00:40 :: Jensen :: Replies: 7 :: Views: 3460
Here is a schematic of such an oscillator, if you have other ideas or other schematic to build a simple UHF oscillator they are welcome.
RF, Microwave, Antennas and Optics :: 08-02-2002 11:00 :: hot_chmock :: Replies: 6 :: Views: 4284
was anybody involved in designing a low phase noise oscillator with varactor/varicap diodes at frequencies around 1 GHz?
links, pdfs or comments very welcome!
RF, Microwave, Antennas and Optics :: 09-18-2002 18:22 :: rfmw :: Replies: 16 :: Views: 4801
How can i make a 15625hz oscilator?
i want to put a ne565 or a 4046 oscilating at that precise frequency, with very small deviation +-10hz
Professional Hardware and Electronics Design :: 01-11-2003 21:12 :: Marmelado :: Replies: 14 :: Views: 3675
I nedd to develop an sqare wave oscillator in the frequency range of about 400 KHz up to 1.5 MHz with only 2 V of power supply.!!!!
I have tested the standard 74hc4046 but the minimum power supply for the oscillator stage is 3 V.....
Please give me some suggestion and good idea !!!!!!
Professional Hardware and Electronics Design :: 01-24-2003 13:09 :: Rfboy :: Replies: 4 :: Views: 1229
Please remember that you should use 3D solid modeler
A/u/t/o/c/a/d LT is only 2D
I think most easy to use is S/o/l/i/d/Works or S/o/l/i/d/Edge. Also Inventor, but I have no experiences.
Yopu can also use M/e/c/h/a/n/i/c/a/l Desktop from A/u/t/o/d/e/s/k
Please note: all model must be solids, not wires.
Do you have licenses for HFWorks? It's i
Electromagnetic Design and Simulation :: 02-19-2003 17:57 :: AN :: Replies: 11 :: Views: 6980
RF, Microwave, Antennas and Optics :: 02-02-2003 09:58 :: uummcc :: Replies: 3 :: Views: 1518
How to programm epson sg-8002 oscillator.
PLD, SPLD, GAL, CPLD, FPGA Design :: 02-26-2003 07:13 :: alexsnow :: Replies: 1 :: Views: 2272
I would like to activate the internal oscillator of the at90s1200 what kind of code should i write?
PC Programming and Interfacing :: 03-19-2003 23:42 :: Marmelado :: Replies: 2 :: Views: 1197
I'm looking for a simple way (formulas or software) to calculate pi filters in a final (PA-HF) to operate in a given frequency and in general how to calculate final power amplifier.
RF, Microwave, Antennas and Optics :: 03-30-2003 04:29 :: jazzyfunk :: Replies: 3 :: Views: 2313
I am looking for any recent articles in low noise
microwave oscillator design
RF, Microwave, Antennas and Optics :: 04-07-2003 16:45 :: gladiator :: Replies: 0 :: Views: 1088
I am looking for any oscillator tutorial ?
RF, Microwave, Antennas and Optics :: 04-07-2003 16:49 :: gladiator :: Replies: 2 :: Views: 1440
I want to khnow some about available hf and wireless modems ( BW,modulation,... ), and design of them
thanks in advance
Professional Hardware and Electronics Design :: 04-21-2003 05:21 :: watson :: Replies: 1 :: Views: 650
Suppose the output frequency of an oscillator depends on a design parameter RX. I want to get a exact frequency ( say 100KHz ). How to write optimization statements if I use hspice for optimization? Output node is names as Y.
The major problem is how to measure the output frequency after transient analysis.
Hobby Circuits and Small Projects Problems :: 06-11-2003 01:03 :: Hughes :: Replies: 0 :: Views: 1276
Could anyone tell me how to construct a high-frequence(200MHz)
circuit if don't use PLL? RC or Ring oscillator can contribute
my wanted? The accuracy can be acceptable on +/- 15% tolerance.
Thanks a lot.
Professional Hardware and Electronics Design :: 06-23-2003 06:04 :: packet :: Replies: 1 :: Views: 2215
I need some good ideas to design a microwave oscillator in the 8 - 10 GHz frequency range
RF, Microwave, Antennas and Optics :: 06-26-2003 12:15 :: zeshan102 :: Replies: 1 :: Views: 1459
does anybody know a suitable transistor for x-band oscillator.
RF, Microwave, Antennas and Optics :: 07-18-2003 06:13 :: zeshan102 :: Replies: 2 :: Views: 1027
I have designed a X-band oscillator at 9GHz. How can I simulate the design in ADS. What is the behaviour of S-parameters at oscillating frequency. I am also having trouble in designing biasing network.
RF, Microwave, Antennas and Optics :: 07-30-2003 05:29 :: zeshan102 :: Replies: 29 :: Views: 6604
I want help about design an equalizer for a multipath, slow fading channel
(exactly ionosphoric channel for HF communication)
RF, Microwave, Antennas and Optics :: 09-08-2003 11:18 :: watson :: Replies: 0 :: Views: 813
has anyone tried this High frequency simulator? :?:
I searched the forum and found only 2 messages concerning HFWork$ 1.5; an older version :(
Looks quite impressive and support website looks quite awesome 2!!!! It could be a strong competitor 2 HF$$.
However, it is offering only a 15 days tria
Electromagnetic Design and Simulation :: 09-16-2003 18:08 :: Element7k :: Replies: 0 :: Views: 1244
I seem to remember seeing a design for something like this using IRF hexfets....
Search for ham hf amplifier irf510 on google...
RF, Microwave, Antennas and Optics :: 09-22-2003 05:47 :: twinsen :: Replies: 5 :: Views: 20656
In choosing an HPA for HF one must know the app; is it digital modulation requiring very high linearity and thus must back off 7-10dB from P1dB(like CDMA)? Or is it like EDGE requiring less backoff? Or perhaps it's RADAR? The app makes all the difference in how to design. BTW, I noticed Motorola now has a 100W CW device with push-pull topolo
RF, Microwave, Antennas and Optics :: 09-23-2003 06:51 :: MoonShine :: Replies: 6 :: Views: 1596
I am trying to simulate an oscillator (4MHz) circuit that consists of a transistor and some discrete components. The only thing that comes out of the simulation is in the order of femto to pico volts. Does anyone know what I am doing wrong?
Software Problems, Hints and Reviews :: 09-24-2003 16:58 :: kleinesmurf69 :: Replies: 4 :: Views: 3213
Hi everybody, I want to have information about designing a Triode Cavity oscillator in C-Band. I don't know where to start. If anybody has information about the topic or any site to suggest it will help very much.
RF, Microwave, Antennas and Optics :: 09-30-2003 14:57 :: huvarda :: Replies: 0 :: Views: 1097
I just want to know if a PIC16F84-04P or PIC16F628-04P oscillator will work with 8MHz crystal if the oscillator fuse is set to _HS while programming? :roll:
Microcontrollers :: 10-02-2003 07:21 :: hadihf :: Replies: 2 :: Views: 1571