| Author |
Message |
    
123upmichigan
| | Posted on Friday, January 24, 2003 - 7:07 pm: | 
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hello was just wondering if anyone can help me out. i am looking for a test quality frequency counter for aligning radios and for general frequency counter use. does copper sell them? also i have a texas star mod v plus and it does not have a rotary dial but a regular toggle in it's place. just connect to the board in 2 places in the front and does not seem to do nothing. i was also wondering if there was a way to make the little modulator so the relay does not chatter on ssb.. anyone got any idea's? |
Znut
| | Posted on Saturday, January 25, 2003 - 12:28 pm: |
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123,
I've been wanting to solve the relay chatter on my Golden Eagle by putting a keying circuit in.
When I open it up and figure out the best way to hook it up to the relay, I'll let you know. It should be virtually the same.
I'll put a jack on the rear of the radio that connects to the mic keying pins in the radio, at the mic jack, I guess. Then put a jack in the amp that hooks to the relay to directly key the relay instead of from the voltage stored in the capacitor. I've tried already to use a bigger cap, it hangs longer but is still unsatisfactory. I definitely want to do this mod before I get on 10 (yeah, key up on HF with my echo, roger beep, and a chattering class C amp!) J/J, mine is AB.
Znut |
Bigbob
| | Posted on Sunday, January 26, 2003 - 9:11 am: |
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You need a capacitor in parallel in the keying circuit about 4.7 to 10 micro farad add a switch and you can switch it in and out. Without looking at the guts I can't tell you where to put it. |
2600
| | Posted on Sunday, January 26, 2003 - 5:05 pm: |
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I definitely DO NOT recommend hooking a cable from an external amplifier to the mike jack of a radio. This is a good way to create "ground loop" currents. Pumping unwanted external current into the ground pin of your mike jack can cause odd squeals, hissing noises, and worse. If you are using a "computer" controlled radio like a 2950, adding the relay voltage to the transmit pin on the mike jack can pop the computer chip. Adding diodes will prevent that, but you still have the risk of unwanted feedback trouble.
For years, we have been doing this with a small switch transistor. The relay coil with the transistor in series with it are connected to the main 13.8 Volt power in the radio. The internal 8-Volt "transmit-only" voltage feeds through a resistor to turn on the transistor, and key the relay. This keeps it all isolated from the mike circuit.
I guess if there's some interest, I should put up a diagram of this trick. Sure beats a foot switch.
73 |
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