murania


JAMES DAVIDSON
 

even with my hearing aids would still like more audio . any one got a mod yet  please /???


ohwenzelph
 

Hi Jim,
I changed Q1 to a BC550C and it works ok, the “beta” on my transistor tester was 483 for the BC550C and 212 for the 2N3904. It might have been a little bit louder but it was certainly not striking (the body of the BC550 has to be turned 180 degrees to get the leads right). So, it might make a little difference....
You can try tweaking the little loop some, it can change the reception significantly if it’s really not right.
i could not find a speaker that produced more audio, and would fit, regardless of how many ohms it was rated.
So far I have not found a way to make it a lot louder, I do think the mods make the volume control go quickly from silent to max volume at about half way round with little or no change before or after.
i considered the limited volume as possibly a positive feature for my daughter when I made one with and for my grandson.
i am not bright enough to figure out how to modify or add to the circuit to make it louder than it is, so if you come up with something please do share it on the list. Thanks & 
73
jer aa1of
franconia nh


ohwenzelph
 

Hi Guys,
Did not like the volume knob behavior after the mods. Seemed to go from none to max over a very short range. Tried detaching the ground end of the volume pot from ground and that led to max vol with no effect from the knob. (Despite my efforts I still really do not understand this stuff.)
So I put a 33k resistor between the ground end of the pot and ground. And I put a 39 k between the ground end of the pot and the opposite, non-wiper, not middle, end of the pot. It is not ideal but I think it’s better. The last third of the rotation is still all just max vol with no change, so there is room for improvement. But.. I think it feels more like a “volume control” than before. If some body finds a better set of values or arraignment then please let us all know.

2nd change: Rewound the antenna coil with litz wire from https://www.mikeselectronicparts.com/product/litz-wire-180-46-44-special-blend/
and messed with the tickler coil a bit.. 

I think maybe its it’s a little bit louder and I may be hearing more stations but that may just be propagation at the moment. 

73’s to all
jerry aa1of
franconia nh 


ohwenzelph
 

Lite wire
After a few days I can say I think this is an improvement.
I can definitely tune more stations than before. Somebody else should give it a try. It might even be enough to consider it as an upgrade to the kit. A bulk buy would make it a bit cheaper.
I did also try making a double loop for the tickler coil. Unfortunately I did them both at the same time. I am not sure if the the winding direction for the ticker coil and the main coil are both in the same direction and need to experiment more with that.
How to tin lite wire:
https://youtu.be/UlHo3Q8gOmI
from 3:00 to 9:50, he has to think how to say in English so I watched it at 1.75 speed but rewatch the actual procedure parts at normal speed. [Do not set denatured alcohol on fire, I burned my finger once doing that with a penny stove, adding more when I thought it was not lit yet (the flame can be nearly invisible) even though my hand went right into running water it was a painful week.] 


ohwenzelph
 

LITZ ( not ”Lite”) wire  (dang spool cheekier!)
looking at my photos, I had messed with the tickler coil before changing the inductor wire, so I think the improvement is truly mostly from the wire change. Also, near every commercial AM radio with a ferrite loop antenna that I have ever seen, used stuff that looked to me like litz wire, at least cloth fiber covered. I don’t recall ever seeing anything that looked like solid enameled copper. 
Side note, I think I needed a couple more turns on the rewind but had cut it too short...
I would love to have someone else try this and report back.
jt aa1of