Bloody Punjabi Radio

Dominic

Weird thing.....I have a number of amps that run together and I use an amp switcher
they are all set up permanently, plugged into same points etc
 9pm every Saturday and all day Sunday (never any other time ) one of them picks up a Punjabi radio station which comes through the speakers very loudly .........I can half defeat it by activating the ground lift button but it then comes out of another amp at a lower volume 
 I can clearly hear the adverts for Travel agents in Southall, grocers, and wedding announcements etc (at least I know where to book my next tickets to India or could gatecrash some pretty spectacular weddings ...)
 Why does this happen ?

mgaw

I was trying out the new Vemuram Myriad fuzz the other day and I had  a foreign radio station belting out of the amp!!

Dominic

I know that pedal...........The Bollywood Boost !

ecc83

Not weird at all Dominic. Without being rude, your country is where WE were at the beginnings of readily available audio technology. Radio Frequency Interference WILL get into amps unless measures are taken to stop it.

I am pretty sure many of the schematics of Blackstar HT pedals have found their way onto the Net by now so have a look at the front ends and output jacks on those and see the LC components used. Cheap shit omits them but they are not allowed to do that here in EU/UK.

Do you know the broadcast frequency of the radio station? Is it Mwave or VHF? If you would like to PM me Dominic I can give you diagrams and things to try. Sometimes external filters can help but usually you need to mod* the amps and pedals.

*Not really mods, Good engineering that should have been part of the original design.

Actually many of the ripped schematics don't show the filters. You are looking for an input choke/inductor and  capacitors. You will also find the input protection Zener diodes. Bet your kit does not have those either!

Dave.

JayGee

Dominic said:

Weird thing.....I have a number of amps that run together and I use an amp switcher
they are all set up permanently, plugged into same points etc
 9pm every Saturday and all day Sunday (never any other time ) one of them picks up a Punjabi radio station which comes through the speakers very loudly .........I can half defeat it by activating the ground lift button but it then comes out of another amp at a lower volume 
 I can clearly hear the adverts for Travel agents in Southall, grocers, and wedding announcements etc (at least I know where to book my next tickets to India or could gatecrash some pretty spectacular weddings ...)
 Why does this happen ?

I’m going to take a wild guess at a pirate station which only operates at the weekend.

Dominic

Wow , all sounds a bit Scientific and well beyond my understanding......I'm guessing it is a pirate station of some kind but obviously it doesn't open the shop til 9 pm on a Saturday evening.
I wouldn't know about VHF or Medium wave and was hoping that there was some kind of simple plug in filter - it doesn't bother me enough to get busy opening amps/modding etc
It probably goes quite well with my Ravish Sitar pedal !

mart

Dominic said:

.... 
 I can clearly hear the adverts for Travel agents in Southall, ...

ecc83 said:

Not weird at all Dominic. Without being rude, your country is where WE were at the beginnings of readily available audio technology. ...

I’m going to make a wild guess that @Dominic’s country is England, in which case where are you based Dave @ecc83 ?

Wazmeister

The question is... did you play along with it ?

Sassafras

Don't fight it, get into that Bhangra beat.

danishbacon

Wazmeister said:

The question is... did you play along with it ?

Was wondering exactly the same thing.

ICBM

Do either of the amps do it individually when they’re not connected together via the switcher?

ecc83

mart said:

Dominic said:

.... 
 I can clearly hear the adverts for Travel agents in Southall, ...

ecc83 said:

Not weird at all Dominic. Without being rude, your country is where WE were at the beginnings of readily available audio technology. ...

I’m going to make a wild guess that @Dominic’s country is England, in which case where are you based Dave @ecc83 ?

I confess I just saw "Punjabi Radio" and assumed the Indian sub! I now see OP is based in London so the whole situation is much easier in that the radio station is probably breaking the law unless the amp kit is some really cheap, imported **** that has not been built with basic filters and has not gone through EM tests.

It USED to be the responsibility of the GPO to track down and prosecute illegal radio transmitters but in these unregulated, privatized days I would not know who TF to turn to.  The company I was a service tech for used to work with the GPO RFI dpt and go CB burner chasing!

Dave.

Dominic

ICBM said:

Do either of the amps do it individually when they’re not connected together via the switcher?

Yes
Switcher is either a Palmer trio or Voodoo labs 4 switch but they both have individual transformers ,ground lifts etc

ICBM

Dominic said:

Yes

In that case it may be coming via the mains wiring, or just so intense that it's being picked up directly, which would imply the pirate transmitter is *very* close.

I'm not normally one for 'reporting things to the authorities' when it does so little real harm as a pirate radio station, but I probably would.

Dominic

Yes ......it is coming from the mains wiring I'm pretty sure ......I guess that they are acting like an arial but I live on a farm surrounded by fields although there are Pylons crossing the fields.....so it's hard to think that it can be that close

ICBM

If you live on a farm, how good is the mains earth connection? If it's just a spike driven into the ground it may not be very effective.

Dominic

I don't know -will have to look at that

ecc83

https://www.google.com/search?rls=com.microsoft:en-GB:IE-ContextMenu&q=guitar+pedal+switcher+schematics&tbm=isch&source=univ&sa=X&ved=2ahUKEwjJ2fyKtffgAhWksaQKHfsnC_gQ7Al6BAgEEA0&biw=1093&bih=522#imgrc=ZUEx10j9S5BW-M:&spf=1552215440331

Cannot find schematics for either of the OP's units but above is a transformer isolated switcher and there is not a shed of evidence of an RF filtering at either input or output. It could of course have been omitted "for clarity" but I doubt it.

Dave.

ecc83

ICBM said:

If you live on a farm, how good is the mains earth connection? If it's just a spike driven into the ground it may not be very effective.

Rather counter-intuitively, one of the things that IMPROVED long and MW radio reception was a good earth! But then I guess nor many here had an old mains radio with aerial and earth "wander" sockets on the back? Or put up a 100 foot aerial down the garden?

Dave.

ICBM

ecc83 said:

Rather counter-intuitively, one of the things that IMPROVED long and MW radio reception was a good earth! But then I guess nor many here had an old mains radio with aerial and earth "wander" sockets on the back? Or put up a 100 foot aerial down the garden?

I did . I made a loop antenna right over the top of my parents' house. I could get stations on the other side of the world on a good day (or actually night).

But I suspect you won't be too surprised by that .

normula1

So did I. I heard about John Lennon's shooting from a short wave radio station in the US