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BASIC TEST EQUIPMENT. What do I need?
#4

There won't be much of any use for a power supply; I dont' recall having used one in the last 40 years on radios.

A high impedance AC Voltmeter (hp 400 series) are a requirement for peaking IF's accurately.

A frequency counter is essential if your signal generator doesn't have a read-out.

An oscilloscope is excellent but you must learn to use it properly. That will take time and practice especially in triggers and what to trigger off of.

A high impedance 10:1 divider probe is essential for use with the scope, AC voltmeter, and counter. Using ordinary wire or coax and clip leads into a circuit will load and add capacitance to whatever you are looking at-and you will NOT be getting the results you had hoped for. The hi-Z probe will always look like a 10Meg resistor (nothing!) to a circuit.

Something not always thought about but very important- a cheap external attenuator that will remain forever on the output connector of your sig gen. 10dB is perfect- it will reduce your signal level to one tenth and protect your sig gen from getting fried when you accidentally make connection to the B+ (high voltage). The attenuator will fry instead of your sig gen (been there, done that).

Your signal generator should go down to 175KHz and be capable of 70% AM; better yet a range of audio to 50MHz. IF's are usually 455-470 KHz, but will go down to 175KHz in some Silvertones- that's the only reason for going down to 175KHz.

Pete AI2V


Messages In This Thread
BASIC TEST EQUIPMENT. What do I need? - by BOB C. - 08-17-2007, 06:35 PM
[No subject] - by Texasrocker - 08-17-2007, 11:23 PM
[No subject] - by calmark - 08-18-2007, 07:37 AM
Equipment needs - by AI2V - 08-18-2007, 08:28 AM
[No subject] - by Ron Ramirez - 08-18-2007, 08:49 AM
[No subject] - by BOB C. - 08-31-2007, 07:07 PM
[No subject] - by signaltracer - 09-01-2007, 06:27 PM
[No subject] - by DeckApe - 08-25-2008, 01:02 PM
[No subject] - by phly guy - 08-25-2008, 05:52 PM
[No subject] - by Alan Douglas - 08-25-2008, 09:44 PM
[No subject] - by DeckApe - 08-26-2008, 12:20 PM



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