SZ123

FM Transmitter Lovers

Author Archive

FM vs AM: What's the difference?

By SZ123 • 八 23rd, 2009 • Category: Radio-Base

FM radio works the same way that AM radio works. The difference is in how the carrier wave is modulated, or altered. With AM radio, the amplitude, or overall strength, of the signal is varied to incorporate the sound information. With FM, the frequenc...



1971 China Peony Radio old photo

By SZ123 • 八 23rd, 2009 • Category: Radio-Base

1971年的10月,北京无线电厂接到了北京市关于在北京饭店及主要星级饭店配备国产高级半导体收音机的任务。那一年,乒乓外交使中美关系迅速解冻,联合国恢复了我国的合法席位。
为...



How is a Radio Wave Emitted?

By SZ123 • 八 19th, 2009 • Category: Radio-Base

OK. So we have a signal that is sent to a radiosmitter's antenna. How does that signal get from the antenna to the air?
Let's first take a look at the signal. The signal is an electic current, and every electric current is actually electrons mo...



4 transistor tracking transmitter (2N3904,2N3906)

By SZ123 • 七 30th, 2009 • Category: Radio-Base
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FM Telephone Transmitter (FM phone-tapping device)

By SZ123 • 七 30th, 2009 • Category: FM Transmitter Diy

Would you like to be able to amplify a phone call so everybody can hear it? Or perhaps you'd like a way to record phone calls for record-keeping purposes. If either idea sounds good to you, then you might want to build the FM Telephone Transmitter des...



3Watt FM transmitter Diy (2N3553)

By SZ123 • 七 27th, 2009 • Category: FM Transmitter Diy

Discrete components of the design of phase-locked loop transmitter 3 to 3.5 W.
This is the schematic for an FM transmitter with 3 to 3.5 W output power that can be used between 90 and 110 MHz.
The circuit has been tested on a normal RF-tes...



BA1404 FM stereo transmitter

By SZ123 • 七 21st, 2009 • Category: FM Transmitter Diy

At the core of a small BA1404 FM stereo transmitter

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Low Power FM Transmitter (BC549x2) Diy

By SZ123 • 七 21st, 2009 • Category: FM Transmitter Diy

by Rod Elliott (ESP)
Introduction
I have had a few inquiries about a low power FM transmitter, and this article should satisfy those who might want to build one.  It is designed to use an input from another sound source (such as a gui...



5Watt FM Transmitter (MRF237)

By SZ123 • 七 21st, 2009 • Category: FM Transmitter Diy

CAUTION! This transmitter is illegal in the Netherlands and in many other countries. The creator of this site is not responsible for the consequences of using this channel. He is also not liable for fines or seizure of equipment. The construction o...



Radio-controlled transmit and Receive DIY

By SZ123 • 七 16th, 2009 • Category: Radio-Base

Part of the Radio-controlled transmit, transmit frequency of 265MHz, 12V power supply, the remote distance of 100M, operating current is only 4mA.
265MHz UHF frequency transmitter is made up of V1 and external components C1, C2, L1, L2, etc. thr...