Ramsey Electronics HR40 manual Alignment

Models: HR40

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Alignment:

Turn on whatever reference signal source you plan to use. This can be a regular transceiver keying a few milliwatts into a dummy load, a crystal oscillator or a signal generator. Or, you can look for a known signal that you have tuned in on another receiver.

If you are without any reference signal whatsoever but have a reasonable antenna , you can use your familiarity with the 40-meter band to make a rough alignment of the receiver.If Ham radio and 40 meters are new to you, here’s a rough idea of what you can expect to hear on this busy band.

7.00 - 7.08 MHz - CW, most of it is fairly fast

7.08- 7.15 MHz - Teletype (RTTY) and digital operation

7.10- 7.20 MHz - SSB voice, many different languages

7.20- 7.35 MHz - general SSB voice operation

NOTE: A miniature transformer alignment tool is used to turn the slugs in L1 and L2. If you do not have one, make one by gently sanding the tip of a wooden match stick, a kabob skewer or other piece of wood or plastic. While it seems that a small jeweler’s screwdriver could be used, be aware that its metallic construction will make adjustment of L2 very erratic and could damage the powdered iron slug. Any kind of metal tip will affect the coils true value, so that the oscillator will run at one frequency with the metal instrument in the coil can, and a completely different frequency by itself.

ˆFor now, set the tuning control to its mid-point. Use the insulated alignment tool to gently rotate the slug in the top of L2. If it starts to get tight , DO NOT FORCE IT! Instead gently rock it back and forth until it loosens up. You should find your 7MHz reference over a range of approximately 6 to 9MHz. The varactor tuning control can cover any 300KHz range chosen within the 6 to 9MHz limits.

ˆAdjust L1 for maximum received signal strength. Now you’re ready to receive on-the-air signals! After you get used to its tuning and performance, you can adjust the tuning control, L1 and L2 to get the exact tuning range you want.

ALIGNMENT HINT FOR ALL DIRECT CONVERSION RECEIVERS:

You will clearly hear the oscillator of your kit - very close to its receiving frequency, if you tune around for it on ANY shortwave radio covering the same frequency range. Even if your shortwave set does not have a BFO (beat frequency oscillator) for CW-SSB, you’ll still hear a powerful ‘hiss or quieting’ when your shortwave receiver is tuned near the frequency of the HR40. Your shortwave receiver is actually picking up the oscillator signal within the HR40!

HR40 15

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Ramsey Electronics HR40 manual Alignment