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Post by Druid Hills Radio on Mar 8, 2017 14:25:32 GMT
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Post by station8 on Mar 8, 2017 22:13:51 GMT
Hi Guys: I can talk about this subject do to I personally took the power supply apart for the Talking house, iam tx.
Here is what to do to fix your hum issues !!!!
1) In my opinion I would NOT cut that brown wire inside the tx it's the internal ground wire !
NOTE: I have tried this it effects your range and is dangerous, NOT having a proper ground to protect
The tx could cause electrical shock/kill you or cause a possible fire risk, Be SMART leave the ground alone !!!!!
2) Replace your power supply with a better filter supply!!
NOTE: Make sure its NOT a switching or poorly built power supply in any shape or form !
Now you can modify the original power supply that comes with the talking house and iam tx
I have done this with mine and cut 99% of the hum out !
NOTE: Make sure you know what your doing before doing this I'm NOT responsible or this site for your mistakes !!!!!!
1) You will need a 5/32 nut driver.
2) Take out the 3 screws. ( 2 on top 1 on bottom on plug side ).
3) look at your power supply output,where wire comes out and goes to your tx.
NOTE: The output side is poorly built this is why you have a bad hum issue !
All you have is 4 diodes and a toriod that all you have on the output side!
4) Replace output with a well design filter and this will stop your hum issues.
NOTE: You can come up with your own design or find power supply filters on the website, and only for the
Technical personal!!
5) Or just get a better power supply for non tech people.
Take careful note when placing your cover back on make sure you do NOT cut / damage the brown wire it's your ground.,
The brown wire comes from 3 rd prong to the ground side of the output section.
Now after placing cover on,NOT PLUGGED INTO AC get a meter and check your ground side to make sure it's still
Connected.
I hope this helps you out
Have a great day station 8
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Post by End80 on Mar 10, 2017 0:01:54 GMT
I have a curious hum with my current configuration which I was not getting before.. Now granted, your thread is talking about Talking houses, and mine is a Rangemaster, but I see no point in starting a new thread on the subject of hum. I'm not particularly concerned about it because my current setup is only temporary, but it is weird. As I've explained in another thread, right now I simply am feeding audio to the transmitter directly from the headset jack of a Windows Surface tablet.. I get a mild but noticeable hum, but here's the weird part; the hum goes away if I have the tablet in my hand or sitting on my lap! It doesn't matter if the tablet is connected to the charger or running off it's internal battery - the hum is there either way, but the moment I put my hand on the tablet the hum goes away -- What the heck is happening?
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Deleted
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Post by Deleted on Mar 10, 2017 0:28:16 GMT
You probably want to run a ground loop isolator on your audio cable. I put them 'in the loop' so to speak for all my unbalanced cables (i.e., running from an audio jack to whatever) and they do make a huge difference in hum reduction.
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Post by End80 on Mar 10, 2017 1:22:47 GMT
Ahh! Yes, I forgot, an unbalanced signal is currently being sent to a transmitter requiring a balanced signal, whereas usually I'm going through processing gear with a balanced output. I've never really grasped the balanced/unbalanced concepts to well, but only know to observe them while putting together an airchain.
But my question is why does the hum go away when I touch my computer? Keep in mind it doesn't matter if my pc running off of battery or if it's plugged into the wall.
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Deleted
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Post by Deleted on Mar 10, 2017 1:54:23 GMT
My Guess
End80 gives a clue as to the cause of a hum: "My question is why does the hum go away when I touch my computer?"
I think it's an RF problem... something... maybe the unbalanced shield of the audio cable... is picking up the transmitter's own RF, and when you touch the computer it changes the tuning of the RF path.
Getting rid of such problems is exactly why you need balanced audio.
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Post by End80 on Mar 10, 2017 2:02:37 GMT
I usually am running balanced, but in the present case I'm running unbalanced as a kind of emergency broadcast to offset the effects of part15 withdrawals. What I mean is that right now it's either unbalanced or nothing at all.
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Post by End80 on Mar 10, 2017 2:07:31 GMT
My GuessI think it's an RF problem... something... maybe the unbalanced shield of the audio cable... is picking up the transmitter's own RF, and when you touch the computer it changes the tuning of the RF path. Oh.. Thanks a lot Carl for spoiling my hope. I thought maybe I somehow acquired a magic touch. Now I know it's not true.. sigh.. I had such great plans instore. |
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Deleted
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Post by Deleted on Mar 10, 2017 2:09:40 GMT
Unbalanced Can Work
My AMT3000 is fed from a 25-foot unbalanced video cable with RCA connector adaptors to BNC connectors and it works very well.
The angle that the cable arrives at can be shifted until the RF interference gets nulled out. I just made that up right now, but it is possibly true.
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Post by Druid Hills Radio on Mar 10, 2017 12:57:49 GMT
Ahh! Yes, I forgot, an unbalanced signal is currently being sent to a transmitter requiring a balanced signal, whereas usually I'm going through processing gear with a balanced output. I've never really grasped the balanced/unbalanced concepts to well, but only know to observe them while putting together an airchain. DHR Question: Why aren't you using the audio module that comes with the Rangemaster.? Converts unbalanced to balanced.But my question is why does the hum go away when I touch my computer? Keep in mind it doesn't matter if my pc running off of battery or if it's plugged into the wall. Answer from DHR: Your body is acting as a decoupling capacitor. |
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