69 Threads found on edaboard.com: Receiver Vhf
That is a long list of questions!
Ferrite beads are used primarily to reduce RF leakage from one side of a unit to the other side. If you had a receiver/transmitter, for instance, there might be power leaking from the transmitter into the receiver along the power supply lines. You would not want to use high Q inductors dropped along the power
RF, Microwave, Antennas and Optics :: 02.09.2008 20:40 :: biff44 :: Replies: 3 :: Views: 1034
Analog Circuit Design :: 25.01.2009 10:54 :: erikl :: Replies: 4 :: Views: 722
I need design data on a S-band (3 GHz) to vhf (144 MHz) down converter to be use in aweather satellite receiver for pictures from geo-stationary satellites
Can anybody help me?
RF, Microwave, Antennas and Optics :: 05.02.2009 14:48 :: klystron :: Replies: 1 :: Views: 728
hello I am constructing a 1Hz to 40MHz broadband receiver and I need a 50MHz low pass filter for receiving only in order to attenuate the unwanted vhf/uhf. the filter needs to allow frequencies from 1Hz to 40MHz to pass.
I have found this and schematic here
RF, Microwave, Antennas and Optics :: 29.08.2009 19:10 :: neazoi :: Replies: 6 :: Views: 2031
what freq do you want ?
is it to be received on a normal TV ?
more than 1 TV or only 1 receiver needed ??
RF, Microwave, Antennas and Optics :: 22.07.2010 21:53 :: davenn :: Replies: 17 :: Views: 2189
Can anyone tell me the difference between a normal antenna and a radar antenna
and what are the principal radar antenna functions ?
How do we feed a radar antena, does the antenna system contain any power unit which feeds DC or AC power ?
there is no difference, the same antenna has a transmitter and
RF, Microwave, Antennas and Optics :: 24.07.2010 03:40 :: davenn :: Replies: 1 :: Views: 1354
Because it's a superhet receiver, the adjacents channel rejection is mainly defined by the IF filter, not the tuner module.
The tuned input filter is responsible for the foreign channel large signal strength.
There are no "silicon tunable filters". Single chip receivers are either using tuned LC filters or operating as wideband
RF, Microwave, Antennas and Optics :: 09.08.2010 15:47 :: FvM :: Replies: 16 :: Views: 3582
problem with transistor based FM transmtter is that output freq. is not fixed . so if u use digital FM receiver such like in ur mobile phone u will be unable to receive signal. so u have to use manual analog radio receiver to receive ur signal. I think a lots of transmitter ckt available on web . one thing is that BC547 is not useful for FM generat
Hobby Circuits and Small Projects Problems :: 12.11.2010 01:38 :: subir.2006 :: Replies: 8 :: Views: 3423
It may be difficult problem. Satcom receivers are often more sensitive to interference than other receivers.
I would advise the following steps:
1. First if possible, try another generator. Have the generator supplier repair it or serviced.
2. Check the generator metal cover for loose parts. Check the power cable connectors and cable itself. It sho
RF, Microwave, Antennas and Optics :: 06.05.2011 14:50 :: jiripolivka :: Replies: 3 :: Views: 372
All CDMA phones have this issue since the transmitter and receiver run at the same time. They have a dual filter known as a duplexer. One filter passes Tx frequency and attenuates at Rx frequency to avoid spraying the Tx PA's broadband noise across the receive band. The other filter is the Rx side path which attenuates the Tx frequency to avoid
RF, Microwave, Antennas and Optics :: 22.05.2011 22:15 :: RCinFLA :: Replies: 10 :: Views: 799
As there are many types of satellites and their purposes, there are many antennas used to receive telemetry data from satellites, to communicate with satellites, etc.
Take low-orbit satellites. They are mostly used for scientific experiments above the atmosphere. Such satellite instruments are either programmed to continuously transmit data to E
RF, Microwave, Antennas and Optics :: 12.09.2011 16:00 :: jiripolivka :: Replies: 3 :: Views: 1351
I need urgent help, pls.
I have searched for the topic but couldn't find any satisfactory answers. Or maybe did not know where to look !..
Shortly, my problem is:
I have been using standart 433 MHz RF receiver-Transmitter kit to transmit and receive some data such as heat, in short range (max. 20 Metres). And it is very sim
Hobby Circuits and Small Projects Problems :: 10.10.2011 12:33 :: Animal_Rights_Now :: Replies: 4 :: Views: 994
This has several useful links in it.
Building your own
Even it recommends buying the receiver, though.
Hobby Circuits and Small Projects Problems :: 25.10.2011 20:44 :: jpanhalt :: Replies: 4 :: Views: 968
Heres a dead simple one, 2 components.
The oscillator can be got from an electronic component supplier such as rs components, the transformer is less common, but if you look through a couple of 70's or 80's tranny radios the red transformer is the one you want, they call it an lt700, electronics surplus houses might have them also.
Hobby Circuits and Small Projects Problems :: 10.02.2012 01:17 :: dr pepper :: Replies: 25 :: Views: 1458
RADAR is basically 1 ms Pulse of RF energy where the resolution is determined by the center frequency, as such tranponders need to switch and detect reflections at the speed of light, something which Op Amps do not have the necessary bandwidth. even at 10Mhz. You need > 1GHz for RADAR.
But with a remote transmitter you can determine Doppler shift
Analog IC Design and Layout :: 17.06.2012 12:28 :: SunnySkyguy :: Replies: 1 :: Views: 459
Hello experts i want to build an wireless audio transmitter and its receiver .
Please guide me ?
which frequency, use ?
the device might be more portable (small size & use less power).
Need minimum range 100meter .
The audio signal from a microphone.
thanks in advance.
Hobby Circuits and Small Projects Problems :: 20.08.2012 13:53 :: thannara123 :: Replies: 2 :: Views: 1159
I am reading a paper and the scenario is the next.
They have a small radio control plane with 6 antennas. The idea is to estimate the attitude angles and I do not know if their solution is realistic or not. Here are the relevant data:
- The frequency is 30MHz. A sinusoidal signal of amplitude 1. The main idea is to measure the phase
RF, Microwave, Antennas and Optics :: 24.08.2012 05:50 :: noether :: Replies: 6 :: Views: 335
It isn't the schematic that causes the problem, it's the construction and choice of component materials. Even a simple single transistor oscillator will work fine under ideal conditions but might drift wildly as temperature changes or something moves nearby. The one you show in post #9 should be OK provided:
1. you stabilize the supply voltage
Analog Circuit Design :: 13.01.2013 04:25 :: betwixt :: Replies: 24 :: Views: 1719
Digital transmitter 100 .What does this 100 mean? is this the gain?i saw this in a report of vhf transmitter and receiver used in aircrafts.
Digital communication :: 17.02.2013 11:20 :: tojeena :: Replies: 1 :: Views: 238