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Ozark Patrol problem


yahoomail@...
 


Karen & I just finished up her Ozark Patrol kit from the Friday night build session.  It seemed to work great when first turned on.  However, when I flipped the BAND switch to the right and we got no REGEN at all.  Any ideas?  Works pretty well with the BAND switch in the left position which seems to be the LOW side.  On the low side we heard WLO coastal maritime station 4 Mhz range, WWV, and an Ontario VE3 on SSB.  Nice.

I twiddled both Gimmick caps but no change on the REGEN problem in the "high" band.

FYI - Karen & I had a blast at OzarkCon this year.  While the kit build ran a bit longer than anyone expected, the kit itself was GREAT!  The programs were, as usual, top quality, and the lunch was a welcome addition.  (Let's keep that as part of the on-going plan if possible.)  One of the best things was that we came home with about 5 kits to build!  We pulled the kitchen table into the living room so we have a work surface right in front of the big-screen TV.  Lots of solder smoke in our near future!

72,

-Ed, WG5F & Karen, W5KKM-


Paul Smith
 

I built a beta kit and there was only one band.
YMMV

de Paul Smith N0NBD

Sent from my iPad

On Apr 17, 2014, at 9:30 AM, <yahoomail@...> wrote:

 


Karen & I just finished up her Ozark Patrol kit from the Friday night build session.  It seemed to work great when first turned on.  However, when I flipped the BAND switch to the right and we got no REGEN at all.  Any ideas?  Works pretty well with the BAND switch in the left position which seems to be the LOW side.  On the low side we heard WLO coastal maritime station 4 Mhz range, WWV, and an Ontario VE3 on SSB.  Nice.

I twiddled both Gimmick caps but no change on the REGEN problem in the "high" band.

FYI - Karen & I had a blast at OzarkCon this year.  While the kit build ran a bit longer than anyone expected, the kit itself was GREAT!  The programs were, as usual, top quality, and the lunch was a welcome addition.  (Let's keep that as part of the on-going plan if possible.)  One of the best things was that we came home with about 5 kits to build!  We pulled the kitchen table into the living room so we have a work surface right in front of the big-screen TV.  Lots of solder smoke in our near future!

72,

-Ed, WG5F & Karen, W5KKM-


W0PWE
 

Ed,
On mine the switch is to the left for the higher frequency band. When switched to the right the 560pf capacitor is added in to the oscillator circuit and the lower band should be selected.

I put my scope on the Q1 collector and did some checking. On the high band it could easily be made to oscillate by turning the regen control. I measured the oscillator at roughly 4.6MHz to 13.5MHz at extremes of the tuning capacitor. 

When I switched to the low band however I could not make it oscillate anywhere in the band with any regen pot setting. I then pulled the 560pf capacitor (C11) and checked it with my AADE meter. It looked good (543pf). So then I tried various capacitors in place of C11. Various combinations of mono ceramic capacitors I had on hand all supported oscillation. Even up to about 700pf it oscillated without trouble. I'm not sure what it is about that 560pf disc ceramic but the oscillator doesn't seem to like it. Low Q maybe? 

My current combination of odd capacitors in C11 measures 526pf and the ends of the dial will oscillate at 3.4 and 4.6 MHz. If you have a different capacitor that you could try in C11 it might be worth a shot. Good Luck.
73 - Jerry


WA0ITP
 

Good catch Jerry!   Is it an NP0 in your kit?


On 4/17/2014 8:15 PM, j.b.hall@... wrote:
Ed,
On mine the switch is to the left for the higher frequency band. When switched to the right the 560pf capacitor is added in to the oscillator circuit and the lower band should be selected.

I put my scope on the Q1 collector and did some checking. On the high band it could easily be made to oscillate by turning the regen control. I measured the oscillator at roughly 4.6MHz to 13.5MHz at extremes of the tuning capacitor. 

When I switched to the low band however I could not make it oscillate anywhere in the band with any regen pot setting. I then pulled the 560pf capacitor (C11) and checked it with my AADE meter. It looked good (543pf). So then I tried various capacitors in place of C11. Various combinations of mono ceramic capacitors I had on hand all supported oscillation. Even up to about 700pf it oscillated without trouble. I'm not sure what it is about that 560pf disc ceramic but the oscillator doesn't seem to like it. Low Q maybe? 

My current combination of odd capacitors in C11 measures 526pf and the ends of the dial will oscillate at 3.4 and 4.6 MHz. If you have a different capacitor that you could try in C11 it might be worth a shot. Good Luck.
73 - Jerry

-- 
72 WAØITP
I love this radio stuff.
www.wa0itp.com
www.4sqrp.com


Jim Kortge
 

On 4/17/2014 9:27 PM, WA0ITP wrote:


Good catch Jerry!� � Is it an NP0 in your kit?
I'll bet it isn't!

72,

Jim, K8IQY


W0PWE
 

It does not appear to be an NP0.
This probably needs some more evaluation. I'm listening to some very readable SSB signals on 75M tonight but it does not seem as sensitive as the higher band does and the regen control is a little more touchy than it is on the higher band.