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As most OLD OLD Hams know, there was a LOT of problems caused on Phone Land lines back then by us Vermin's.

It was RFI.

As a kid and youngster the Neighbors Never Believed that I should even be running my Ham radio.

If they would let me, I would take the cover off the phone lines coming into their houses, and put Disk Caps on the lines.

I went every way, line to line, and lines to box ground.?? That usually fixed the problems.? I think the caps were about a dime?

Way later, I? ferrite beads became available.? Thats what I did to my phone when I started running big power.

The good ol' days, everyone has to get there someday!

73's

Mike, WA6ISP

Perhaps we need to have a sep[erate power wired from the building input thro a metal conduit and provicde an additional emi filter for that right at the load point.. Obviously the equipment ground would be connected to that .

?? Perhaps these are general precautions even the manufacturer prescribes.

sarma

vu3zmv

?

Regards
MVS Sarma
?

On Thu, Feb 8, 2018 at 10:23 PM, Dave Bottom <ars.kd6az@...> wrote:

Even my Novice 75W transmitter would light the hall light at night each time I keyed the rig.

Reversing the switches at each end of the hall made it non resonate on 40M. ?

Probably saved some RF to be radiated too.? LOL

Dave WI6R

On Feb 7, 2018, at 9:15 AM, Michael Hagen <motdog@...> wrote:

Yes, it depends on input Z of the amps.? I remember tube amps.?? I built a big stereo in the 60's, they had Hi Z so low values worked.? I have a great story....... My neighbors had a water heater system with a big water holding solar panel on the roof.? When I fired up the SB200 or 220, it cycled their water pump.? They figured it out!?? They heard me Yelling on the Mic during a DX Contest!? They put 2 and 2 together.

I had to go on the roof and put .1uF? on all their control switches and wiring!?? It was a perfect 20 Ant. up there.

73's

Mike

?

On 2/7/2018 8:44 AM, Mvs Sarma wrote:

Mice,

?I had these experiences that old? Inveterted audio electronic telephones instruments called secraphones installed for VIPs? close to Radio Transmitters? used to misbehave.

?We immediately used to have a capacitor across the Mic module and telephone line Inop=put close to active components to byepass RF.

?You are right that even 1000pF would do.

?But afterall the audio at Volumen control point is coupled with 1 to 5uF capacitors.

?hence i thought even 0.1uF would not deteriorate audio.? The induction could be internal to amplispeaker also and thro power mine that powers the ampli speakers.

?Thu8s? I suppose that byepaasing audio at volume cotroll stage is better.

?regards

?sarma

?vu3zmv

??

Regards
MVS Sarma
?

On Wed, Feb 7, 2018 at 8:53 PM, Michael Hagen <motdog@...> wrote:

Might try looping lead (leads?) to amp thru a ferrite, or get the split clamp on ones, close to were it goes in the amp?

Wrap up in a coil any extra length of the cable.? Makes a common mode choke.

As Sarma says, maybe a 100 - 1000 pF bypass on each input?

73's

Mike, WA6ISP

On 2/7/2018 6:45 AM, Mvs Sarma wrote:

i imagine that Prabha jee

?Pleace a 01.1uF capacitor on ech channel, at the middle pin of Violume control to ground. It would byepass the RF induced in the speaker connecting cable.

? Aduio would disappear.

All the best

?sarma

?vu3zmv

Regards
MVS Sarma
?

On Wed, Feb 7, 2018 at 7:00 PM, Praba Karan <vu3dxr@...> wrote:

external amplispeaker...

i heard audio even volume down bottom.

Virus-free.

On Wed, Feb 7, 2018 at 6:18 PM, Mvs Sarma <mvssarma@...> wrote:

Is it external speaker or external amplispeaker?

Regards
MVS Sarma
?

On Wed, Feb 7, 2018 at 5:05 PM, Praba Karan <vu3dxr@...> wrote:

This issue is from microbitx

--

D.Prabakaran?

VU3DXR

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...