Build Mobile Apps With Zero Coding
The amplified 6 meter signal is mixed at the gate of a 2N3819 FET mixer with the local oscillator signal, generated by a crystal controlled 2N3819 FET overtone oscillator operating at 49.5 MHz This produces a difference frequency of 1.0 MHz which is in the middle of the broadcast band, making the converter ideal for mobile applications. If a 7 MHz difference frequency is desired, a 43.5'MHz crystal is used and the 3900 pf capacitor is the mixer drain tank circuit is changed to 100 PF
The power supply is built in for 117V ac operation, plus the usual 12V dc power cord for mobile use, A little battery test button on the front panel iets you check the battery condition. This test button may not be of great interest for mobile applications, but if the unit is used in conjunction with the accessory CBP-12 Comcraft battery pack, it will tell you how things are going. This battery pack is automatically recharged by the ac supply, by the way.
The all-solid state FT-7 transceiver provides high performance on the BOM-10M bands. Operating on upper or lower sideband and CW, the compact package provides many features engineered for convenience while mobile. A single knob provides all transceiver tuning, and the state-of-the art noise blanker minimizes impulse-type noise found In mobile applications. The FT-7 is designed for operation directly from your car's 12 volt battery or from its matching DC Power Supply.
Eventually a ham discovers the gain, and especially the quieiness on receive,, of loop antennas, and plans to construct one. Soon enough it becomes apparent that loops for the bands beiow 20 meters arc impossibly large. A square loop on 40 meters (7.15 MH i. for example, needs sides about 35 feet long, which may be unreasonably large to erect, especially in the vertical plane. However, a loop, or any antenna, can be made physically smaller while maintaining lull electrical size, Hi is can be accomplished with loading coils, as is frequently done in mobile applications. Unfortunately, coils do introduce some loss. Another approach is to reduce the size of an antenna, e.g. cause it to be resonant above the desired frequency by mechanical shrinking, and then capaciiively stretch11 it. so as to achieve the proper electrical length ior resonance. 'Hie latter is the approach taken here.
The IC-21 has so many nice features that it is difficult to decide which is the most desirable. It has an ac supply built in and will operate from either 115V ac or 13.6V dc, making it a dandy unit for both base and mobile applications . . , and particularly valuable to the operator who wants to be able to use one rig both in the car and at home.
R now wipe the egg off my face and present my slncerest apologies to my friends, not to mention the poor tortured soul in the booth- This is one of the best two-meter rigs have ever used Kenwood has designed this rig to be at home in both base and mobile applications, which is no minor undertaking.
The July 14, 1983 issue of Electronics magazine has an article on Ceramic-Filled Resonators as a low-cost solution to building filters for 800-MHz land-mobile applications. It uses six 10mm varisonators for a receiving filter, four for a transmitting filter. The two filters can be com
A high quality DTMF-encoder and keyboard designed exclusively for land mobile applications. Pipo Communications has developed a new keyboard for the land mobile industry, the P-7 Series of 12-key touchtone encoders. They come equipped with steel keys and sealed Gold Dome contacts. The miniature design witl fit most radios. The encoders aflow output level adjustment.There isn't any RFI, bu there is very low distortion - High Audio Output win dnve any radio. The wide operating voltage range is 4 - 16 vdc, Current requirements are low 1 mA in standby and 6 mA keyed at Volts.
Living With Android
Get All The Support And Guidance You Need To Finally Be A Success At Using Android. This Book Is One Of The Most Valuable Resources In The World When It Comes To Playing With the Hottest Android Tablet.