BA datasheet, BA circuit, BA data sheet: ROHM – Fm Stereo Transmitter,alldatasheet, datasheet, Datasheet search site for Electronic. Page 4. Page 5. This datasheet has been downloaded from: Datasheets for electronic components. Part, BA Category, Communication => Freq/Signal Converters/Generators. Description, FM Stereo Transmitter. Company, ROHM Electronics. Datasheet.

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Running the iron tip along the isolated piece of copper loosens the glue sufficiently for the Cu to be peeled off with the ba1044. Capacitor C2 and resistance R1, protect the circuit from auto datashet. Alignment of the circuit is very easy.

Use the FET to give you give the centre positions of its’ mounting holes Take everything to bits again. It is the ideal project for the beginner who wishes to get started in the fascinating world of FM broadcasting and wants a good basic circuit to experiment with. Use two 15 turn pots on the input signals to bring the level down.

BA1404 Datasheet PDF

It has a bit of noise, filtering is not sufficient, but otherwise it can be made to work extremely nicely. Calibrate the network analyser. But range is significant watch those feds. Who is this design for?

BA Datasheet(PDF) – Rohm

Thanks to the use of two stages, the dztasheet can be driven to full power with less than 1 watt driving power, so that a large gain margin results in this transmitter. The circuit board consists of a piece of fibre glass PCB printed circuit board material clad with 1oz Cu copper each side. I then switched to slow sweep and used a calibrated RF power meter to accurately measure the RF output power.

The chip will get destroyed if it is operated on any voltage higher than 3. Q1 will amplify the input signal from 50mW to about mW. F1 can be substituted with a coil as L4, but in my test I found that the ferrite pearls gave best performances.

Knowing the RF output power and gain accurately allowed me to calculate the input power to the power amplifier. A amplifier of medium force RF for the FM, is always essential for the amateur that wants it strengthens some small transmitter, that likely it has already it manufactured! Make sure you’ll end up with the drain on the right side. You may have to disconnect L4 and L5 while you are fitting the FET, but don’t disconnect R3 as this provides static protection for the device.


Keep those two transistors cool, they can die quickly in this circuit. L2 is nit a critical component and any coil from uH will do the job. Rear panel fixings are held with M3 nut and bolts, and panels that join to the heatsinks are held by M4 bolts tapped directly into the heatsinks so no additional brackets are required. The lead with the slash is the drain, and is to the right Low Pass Filter Testing Any RF power amplifier must be followed by a low pass filter LPF to reduce the harmonics to an acceptable level.

Intra-stage matching is done by C1, C2, and L1. By minimising the input return loss you will minimise the passband transmission loss and passband ripple.

Using the excellent Faisyn shareware filter design utility available from FaiSyn RF Design Software Home Page allows these trade-offs to be easily investigated, and I settled for a passband ripple of 0. Make sure it can take up to W, else it will be a hot resistor. Bipolar VHF power transistors have a severe affinity for low frequency self-oscillation. I would get rid of C12, it is not necessary since C2 blocks the DC between stages. This has the advantage of stunningly low Rds and hence high efficiency, but does nothing for linearity or capacitance.

On the HP C for this application I normalise S11 into a open circuit and do a through calibration on S21 with 40dB of attenuation in line. Liberal use of ferrite beads and feedthru capacitors are on all RF detector, fan control and SWR control circuits.

This program also calculates the filter values for you, and outputs a netlist in a format suitable for inputting into the most popular linear circuit simulators. You have to understand that it radiates god knows where, you will be making a lot of interference! As this design is wideband, this constrains the passband ripple to a level such that the passband return loss does not become to horrible. L6 mostlikly can be optimized, but is most likely not that critical to the overall performace of the amp.


The version datashfet was 6. Alternatively, if you managed to measure you inductors well enough by other means, you bz1404 just assemble the filter and leave it at that, with no further adjustment. This is a pretty conventional design, using bipolar bw1404 in a tuned class C circuit.

As mentioned below, the LPF datashest are soldered directly to the tabs of the metal clad capacitors. Component choices As the input power is only half a watt, standard ceramic capacitors and trimmers were used in the input matching circuit.

The top and bottom panels sit in ridges cut into the heatsinks with a table saw, and then the front and back panels just bolt into the end fins.

No PLL, but stability is excellent. This is an attempt to improve the final harmonic rejection, by reducing coupling between the inductors that form the output match ba104 the inductors making up the LPF.

The inductors were made from 18 SWG standard wire gauge tinned copper wire. F1 with C2 will act as an impedance matching for Q1.

C4, C5 and L4 forms an input matching unit for the transistor. The output power is about 1. FM radio amplifier 25W A simple 25W fm radio amplifier used as a final stage for a 2.

This amplifier is based on the transistor 2SC and 2N Use a very good headsink because this transistor get very hot: Set all trimmers to centre of their range. Solar charger Coils values: Having tuned for minimum passband return loss, the stopband attenuation takes care of itself, you shouldn’t tune for it as you will mess up the passband insertion loss.