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Cricket 30


John - KK4ITX
 

David,

Great to hear that you were working the 40m Cricket....... any contacts ?

John
KK4ITX 

Visit:  www.zaarc.org.   👁

On May 16, 2020, at 17:19, David Kukulka, AB9BZ <dkuk@...> wrote:

With the warmer weather, I decided to take the cricket40 outdoors. I setup in my detached garage, I had no Hum at all!! I'll have to plan on getting the rest of my contacts outside of the shack. Thanks for a fun rig 4SQRP!!
73 ab9bz


David Kukulka, AB9BZ
 

With the warmer weather, I decided to take the cricket40 outdoors. I setup in my detached garage, I had no Hum at all!! I'll have to plan on getting the rest of my contacts outside of the shack. Thanks for a fun rig 4SQRP!!
73 ab9bz


Jeff Peters <k9jp.radio@...>
 

Excellent David,

Thanks for the suggestion and all your help on this matter.

72, Jeff K9JP


On Sat, Apr 25, 2020 at 7:55 AM David Kukulka <dkuk@...> wrote:
I found that a fixed resistor is not good if you are going to use different crystals, The taller can crystals put out a stronger signal and need more resistance. The shorter can crystals will not oscillate with the higher resistance. I ended up with only the 10k trimmer potentiometer in place of R1 and adjust it for minimum acceptable hum. 73 ab9bz


David Kukulka, AB9BZ
 

I found that a fixed resistor is not good if you are going to use different crystals, The taller can crystals put out a stronger signal and need more resistance. The shorter can crystals will not oscillate with the higher resistance. I ended up with only the 10k trimmer potentiometer in place of R1 and adjust it for minimum acceptable hum. 73 ab9bz


Jeff Peters <k9jp.radio@...>
 

Hello David,

Just a thought.  I had the 80 meter cricket a few years ago.  Just reviewed the 80 meter schematic and see that the 80m version had a 1K ohm resistor for R1
The 40m schematic shows 470 Ohms for R1, So, I think, you are correct placing a 10K or even a 4.7K resistor in place of the lower value (470) R1.

72, Jeff K9JP


On Fri, Apr 24, 2020 at 6:28 PM David Kukulka <dkuk@...> wrote:
I have a 40M Cricket with the same problem - the hum is so loud that I can barely hear the station getting back to me (I have 2 q's so far).
I decided to experiment a little after seeing your post. I first tried replacing the coil L4 with varying resistor sizes, I had quiet receive, but no or very little power output. I ended up replacing L4 with a coil that I wound - but had marginal improvement. I then suspected that the crystal oscillator is probably overdriven, so I placed a 10k potentiometer in series with R1, adjusted it until the hum dropped off and it seems to be fine now, RX sigs are much clearer, even with the pot maxed at 10k - I'll probably just pull R1 and place a 10k in its place, - TX is still .7 W. I hope this helps. 73 ab9bz


David Kukulka, AB9BZ
 

I have a 40M Cricket with the same problem - the hum is so loud that I can barely hear the station getting back to me (I have 2 q's so far).
I decided to experiment a little after seeing your post. I first tried replacing the coil L4 with varying resistor sizes, I had quiet receive, but no or very little power output. I ended up replacing L4 with a coil that I wound - but had marginal improvement. I then suspected that the crystal oscillator is probably overdriven, so I placed a 10k potentiometer in series with R1, adjusted it until the hum dropped off and it seems to be fine now, RX sigs are much clearer, even with the pot maxed at 10k - I'll probably just pull R1 and place a 10k in its place, - TX is still .7 W. I hope this helps. 73 ab9bz


Dale Holloway, K4EQ
 

Hi Jerry. I built my 30m Cricket several months ago and had the same problem. After carefully inspecting it several times I couldn't find where I messed up, so I put it aside and haven't touched it since. Hopefully, someone here will have a suggestion or two so we can both put this neat little radio on the air.

Dale Holloway, K4EQ


Jerry
 

I built a Cricket 30 kit some time ago and just put it on the air. When I turn it on it sounds ok for about one second and then hums very loudly and does not change. It has full power output. Any ideas?

Jerry
W9YJI