Difference between revisions of "4A"
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Like many home-assembled projects - this unit had no cover, top, sides or back. | Like many home-assembled projects - this unit had no cover, top, sides or back. | ||
== As Advertised == | == As Advertised == | ||
| − | The 4A was first introduced in the April-August issue of <i>Collins Signal</i> magazine. | + | <center><b>The 4A was first introduced in the April-August issue of <i>Collins Signal</i> magazine.</b></center> |
[[File:4A m.jpg|right|Its first appearance.]] | [[File:4A m.jpg|right|Its first appearance.]] | ||
| − | + | The 4A transmitter marks the entry of the COLLINS line in the extremely low-priced field. The 4A uses a 47 crystal oscillator and parallel 46's in the power amplifier permitting an output of 18 to 20 watts on 1.7, 3.5 or 7 me. The power amplifier is operated on the crystal frequency in each case. Despite its low cost, the 4A embodies the mechanical and electrical refinements found in the larger COLLINS transmitters. A separate power supply is used for the oscillator to reduce frequency "chirp." Standard COLLINS plug-in coils are employed. A single Weston meter is provided with a switching arrangement to read plate and grid currents. The 4A is ideal for an amateur who wants to start out with a minimum investment and yet have a transmitter which will deliver a high quality C. W. signal. The 4A can also serve as a stand-by transmitter in a high-powered station to be used when full power is not required. | |
Really surprising results can be obtained and amateurs who are accustomed to think in terms of kilowatts can get a great deal of service and amusement from one of these little transmitters. | Really surprising results can be obtained and amateurs who are accustomed to think in terms of kilowatts can get a great deal of service and amusement from one of these little transmitters. | ||
Revision as of 20:56, 30 March 2020
This Amateur Radio Transmitter was introduced in the October 1933 issue of QST. It is a crystal-controlled CW-only transmitter capable of 20 watts RF output. The crystal and associated band-changing coils were plugged from the top of the unit.
The 4A was a kit, all parts included, however, you were responsible to purchase the tubes separately.
Construction
Like many home-assembled projects - this unit had no cover, top, sides or back.
As Advertised
The 4A transmitter marks the entry of the COLLINS line in the extremely low-priced field. The 4A uses a 47 crystal oscillator and parallel 46's in the power amplifier permitting an output of 18 to 20 watts on 1.7, 3.5 or 7 me. The power amplifier is operated on the crystal frequency in each case. Despite its low cost, the 4A embodies the mechanical and electrical refinements found in the larger COLLINS transmitters. A separate power supply is used for the oscillator to reduce frequency "chirp." Standard COLLINS plug-in coils are employed. A single Weston meter is provided with a switching arrangement to read plate and grid currents. The 4A is ideal for an amateur who wants to start out with a minimum investment and yet have a transmitter which will deliver a high quality C. W. signal. The 4A can also serve as a stand-by transmitter in a high-powered station to be used when full power is not required. Really surprising results can be obtained and amateurs who are accustomed to think in terms of kilowatts can get a great deal of service and amusement from one of these little transmitters.
