Needed assistance for NS-40?


Jason - WV3V
 

Howdy Gang, 

I recently put together the NS-40 from the simple schematic online and am having a bit of trouble getting the little rig to transmit properly. I would my own coils (I have an L/C meter), and used manhattan style design.  I'm at a lost as to why it's not transmitting. 
I did have a misplaced cap and fixed that. I also replaced both transistors, and some of the other caps to higher voltage ones. I removed one of the coils, and believe that I have everything else connected properly. I am not sure where else to look for issues. 

Any and all assistance is greatly appreciated. 

Jason, WV3V


Tom Sevart
 

On 11/25/2021 02:09, Jason wrote:
Howdy Gang,
I recently put together the NS-40 from the simple schematic online and am having a bit of trouble getting the little rig to transmit properly. I would my own coils (I have an L/C meter), and used manhattan style design.  I'm at a lost as to why it's not transmitting.
I did have a misplaced cap and fixed that. I also replaced both transistors, and some of the other caps to higher voltage ones. I removed one of the coils, and believe that I have everything else connected properly. I am not sure where else to look for issues.
Any and all assistance is greatly appreciated.
The very first thing I'd check is to make sure there's a good connection on the crystal. No crystal = no oscillation.


--
Tom Sevart N2UHC
St. Paul, KS

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Bobby Drummond
 

After checking the crystal connection (as mentioned in the previous email) can you confirm if the oscillator is working?  

Can you hear the oscillator working in a nearby receiver when you key the transmitter?

Bobby - AK4JA


On Thu, Nov 25, 2021 at 9:09 AM Tom Sevart <tmsevart@...> wrote:
On 11/25/2021 02:09, Jason wrote:
> Howdy Gang,
>
> I recently put together the NS-40 from the simple schematic online and
> am having a bit of trouble getting the little rig to transmit properly.
> I would my own coils (I have an L/C meter), and used manhattan style
> design.  I'm at a lost as to why it's not transmitting.
> I did have a misplaced cap and fixed that. I also replaced both
> transistors, and some of the other caps to higher voltage ones. I
> removed one of the coils, and believe that I have everything else
> connected properly. I am not sure where else to look for issues.
>
> Any and all assistance is greatly appreciated.

The very first thing I'd check is to make sure there's a good connection
on the crystal.  No crystal = no oscillation.


--
Tom Sevart N2UHC
St. Paul, KS

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73 de AK4JA


Jim, N5IB
 

Hi Jason,

A while back I undertook the same project, to use as a test platform for the Bayou Jumper, whose Tx is the same circuit. Never got it to work either. I had some chats with NM0S, the designer, and we surmised there is something magical going on with the PCB inductors that toroids just won't duplicate.

Please keep us posted if you succeed in getting it going, as that would be a step along the path of putting the BJ on other bands.

Jim, N5IB


OwlCricker - K7ULM
 

Keep up the good work gentlemen.  Having a multi banded Jumper like the Paraset would be awesome.  Doing Fox Hunts across the bands with be amazing.  This stuff is too much fun and I am Thankful for all the guys who can design all these great toys.  TNX to all. 72
K7ULM 

On Thu, Nov 25, 2021, 7:28 AM Jim, N5IB <n5ib@...> wrote:
Hi Jason,

A while back I undertook the same project, to use as a test platform for the Bayou Jumper, whose Tx is the same circuit. Never got it to work either. I had some chats with NM0S, the designer, and we surmised there is something magical going on with the PCB inductors that toroids just won't duplicate.

Please keep us posted if you succeed in getting it going, as that would be a step along the path of putting the BJ on other bands.

Jim, N5IB






Robert West
 

Two thoughts: 1) the on-board coils may provide for extra coupling that toroids do not; 2) check the crystal itself. Once spent hours on an HW-101 and finally sent it back to Heathkit. It was a bad crystal.


On Nov 25, 2021, at 8:40 AM, OwlCricker - K7ULM <dickw299@...> wrote:


Keep up the good work gentlemen.  Having a multi banded Jumper like the Paraset would be awesome.  Doing Fox Hunts across the bands with be amazing.  This stuff is too much fun and I am Thankful for all the guys who can design all these great toys.  TNX to all. 72
K7ULM 

On Thu, Nov 25, 2021, 7:28 AM Jim, N5IB <n5ib@...> wrote:
Hi Jason,

A while back I undertook the same project, to use as a test platform for the Bayou Jumper, whose Tx is the same circuit. Never got it to work either. I had some chats with NM0S, the designer, and we surmised there is something magical going on with the PCB inductors that toroids just won't duplicate.

Please keep us posted if you succeed in getting it going, as that would be a step along the path of putting the BJ on other bands.

Jim, N5IB






Bobby Drummond
 

If coupling between the PC etched coils figures in / is at the root of the problem, then I would redo the output and configure the PA using this page's Class E circuit calculator to supply new values for the LC components in the PA circuit.

See link below that is a URL from WA0ITP:


I have used it before and it's excellent.

  • If I were to do so, I would probably isolate the 2N700 oscillator's source connection from the PA via a 100 pf capacitor and install a 1N4148 diode in parallel with the PA's gate.  That means that the gate connection of the PA would have one end of the 100 pf capacitor mentioned above and the 1N4148 diode connected there.  Might also be a good idea to install a small ferrite in series with the 100 pf capacitor before connecting it to the gate to prevent unwanted oscillations, spurs, etc.

I know that this would be a radical departure from the original but it might be the easiest solution since trying to figure it out otherwise could end up being very frustrating and possibly fruitless.

Bobby - AK4JA


On Thu, Nov 25, 2021 at 10:28 AM Robert West via groups.io <west_robert_l=yahoo.com@groups.io> wrote:
Two thoughts: 1) the on-board coils may provide for extra coupling that toroids do not; 2) check the crystal itself. Once spent hours on an HW-101 and finally sent it back to Heathkit. It was a bad crystal.


On Nov 25, 2021, at 8:40 AM, OwlCricker - K7ULM <dickw299@...> wrote:


Keep up the good work gentlemen.  Having a multi banded Jumper like the Paraset would be awesome.  Doing Fox Hunts across the bands with be amazing.  This stuff is too much fun and I am Thankful for all the guys who can design all these great toys.  TNX to all. 72
K7ULM 

On Thu, Nov 25, 2021, 7:28 AM Jim, N5IB <n5ib@...> wrote:
Hi Jason,

A while back I undertook the same project, to use as a test platform for the Bayou Jumper, whose Tx is the same circuit. Never got it to work either. I had some chats with NM0S, the designer, and we surmised there is something magical going on with the PCB inductors that toroids just won't duplicate.

Please keep us posted if you succeed in getting it going, as that would be a step along the path of putting the BJ on other bands.

Jim, N5IB







--
73 de AK4JA


Jason - WV3V
 

I resoldered the crystal directly and not hearing it on a local rig. Also tried an SDR, and still nothing. 

Jason WV3V


Jason - WV3V
 

I never was able to get it going and have it on the back burned ATM. I did make VK3YE's bread board design and have it working on 80 and 40 M. However, that too has an issue with the BD139 getting overly hot and going QRT. This is with a 12V supply. I removed the old transistor, added a 100uh inductor, and changed out the supply to a 9v and it works again. 
However, with the 12v supply I was able to hear my signal on 40M this afternoon. But since moving to the lower power source, I now am not able to hear myself on the "local" SDRs (UT, AZ, CA).

This is good stuff to keep the brain active for sure, 73's. 

Jason Wv3v


N0KNS
 

They never sent me a schematic, for my Cricket 40, just parts.


AG1P Ron
 

http://www.4sqrp.com/cricket40.php

 

Just scroll down to the documentation section

72 - Ron - AG1P

 

From: main@4SQRP.groups.io [mailto:main@4SQRP.groups.io] On Behalf Of N0KNS via groups.io
Sent: Saturday, November 27, 2021 12:07 AM
To: main@4SQRP.groups.io
Subject: Re: [4SQRP] Needed assistance for NS-40?

 

They never sent me a schematic, for my Cricket 40, just parts.


N0KNS
 

so I'm not the only night owl...

Please forgive my frustration.
I was looking at that page, when your e-mail was sent.  Thank you very much.  Tomorrow, we'll see if that old soldering iron still has what it takes.  Then to rework my antenna, it's been so long, since I touched a key.  73s 


-----Original Message-----
From: AG1P Ron <ag1p@...>
To: main@4SQRP.groups.io
Sent: Sat, Nov 27, 2021 2:26 am
Subject: Re: [4SQRP] Needed assistance for NS-40?

 
Just scroll down to the documentation section
72 - Ron - AG1P
 
From: main@4SQRP.groups.io [mailto:main@4SQRP.groups.io] On Behalf Of N0KNS via groups.io
Sent: Saturday, November 27, 2021 12:07 AM
To: main@4SQRP.groups.io
Subject: Re: [4SQRP] Needed assistance for NS-40?
 
They never sent me a schematic, for my Cricket 40, just parts.