If I connect this radio to my commercial radio, the carrier leakage will drive S meter to about S9 in CW mode. Pretty interesting and it could be used for S meter calibration?
Since the Li-Po battery pack of correct size is not easy to find, I modified the circuit a little bit to be compatible with rechargeable Ni-MH battery of 8.4 volt. The amber LED is used to decrease supply voltage about 1.8V. The overall current of about 6mA will be good for the LED, and it also can be used for power supply polarization protection. I also found 300 ohm will not be good for his radio since 1uf will filter too much higher side of audio spectrum. I also found the iPhone headset has impedance a bit more than 40 ohm and it is good for higher gain in this circuit.
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If I may, I would call it inline receiver or TTR (Tiny Toy Receiver). The reason for inline is that it is actually connected between antenna cable and headphone cable.
I have plenty in stock. I am selling at 1 USD each.
Thanks,
Adam
在 2018年10月15日，下午12:50，Rob via Groups.Io <roomberg@...> 写道：
I am guessing these are no longer manufactured. More translations landed me with this image:
On 10/15/2018 12:45 AM, Rob via Groups.Io wrote:
Did you hand craft or buy the DIY7-7 coil?
On 10/15/2018 12:07 AM, Adam Rong wrote:
Correct. The 1uf will filter the supply. 64 ohm means 32 ohm + 32 ohm. If you use voltage like 6V or higher, you can also use 300 ohm + 300 ohm like HD600 to achieve higher gain.
I know it is hard to believe but just give it a try and let me know if something goes wrong.
Thanks,
Adam
在 2018年10月15日，上午11:41，Rob via Groups.Io <roomberg@...> 写道：
I pu tthe images here just for discussion. I cut out the Xed parts..... and got this:??
Am I reading this correctly?? PLUS VOLTS? to the NE602 is after the speaker? and what is 64-600 ohms mean??
