Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
Search
Recorded Scope levels Xmit Bitx20a
Surely you've seen these Ron. Specifically but the transmitting video goes through a lot of the webpage process.
toggle quoted message
Show quoted text
I don't have waveforms for the linear. It's hard to take them. Leonard --- In BITX20@..., "ronbaechle" <ronbaechle@...> wrote:
|
Thanks Leonard I remember watching the Videos but I didn't remember seeing the pictures of the xmit waveforms.I borrowed a scope and im looking at my Bitx20a. Thanks for the direct link. Ron
toggle quoted message
Show quoted text
--- In BITX20@..., "Leonard" <dredger@...> wrote:
|
The waveforms should get you to a stage that isn't working. Or it lets you say the stage is good if you have the waveforms. A good physical inspection and transistor voltage checks should get you the rest of the way. Between the hard copy version and the transnitter troubleshooting video, you even get a fair circuit operation description. The pair go very well together as the video uses the hard copy and gives some extra info.
toggle quoted message
Show quoted text
Leonard --- In BITX20@..., "ronbaechle" <ronbaechle@...> wrote:
|
Leonard what happened rig was working fine and then R83 pot wouldn't adj high enough. I did check all the transistor voltages.The last scope picture of Q20 I will check,but any idea what level out of Q3 and Q18 and Q19. I haven't looked at what is the purpose of Q3.Maybe you can tell me without me searching. Thanks Ron
toggle quoted message
Show quoted text
--- In BITX20@..., "Leonard" <dredger@...> wrote:
|
At the junction of Q20-R83 you ought to have at least 800mv's pk-pk with 50mv's audio into the mike jack. If you have that, the problem will be in the PA. You shouldn't have to turn R83 up more than about 3/4th to get 12 watts out. If you have the 800mv's, I'd go back and redo the pa bais adjustments.
toggle quoted message
Show quoted text
Leonard --- In BITX20@..., "ronbaechle" <ronbaechle@...> wrote:
|
Hi Leonard Yes had about 800mv Q20 and retuned and it started working again full output!!! Thanks Ron PS. audio xmt great also
toggle quoted message
Show quoted text
--- In BITX20@..., "Leonard" <dredger@...> wrote:
|
800mv's at Q20-R83 pretty much says everything before that is working fine. I've had a couple of 20a's that didn't put out and after redoing the pa bias's worked fine.
toggle quoted message
Show quoted text
Leonard --- In BITX20@..., "ronbaechle" <ronbaechle@...> wrote:
|
to navigate to use esc to dismiss