Why am I picking up a faint radio transmission

The other day after I finished playing some records and the turntable was off I noticed that I could hear a faint noise coming through the speakers when I turned up teh volume it sounded like a radio transmission. I have played about with moving power supplies and made sure that no interconnect is touching a power lead but the issue persists. Does anyone know what the cause is and if there is anything, which a low tech person like me, who is not clued up on electrical engineering can do?

My set up is a Gyro deck with SME309 into a Lehman Black pre amp and then connected via the RCA connection into the AUX2 out on a NAC 122x , power amp is the 150x

Is it just from the phono or do you hear it regardless of which input is selected on the pre-amp? If on all inputs, do you still get it when the pre-amp is muted?

Thanks for the quick reply.
I have just muted the pre amp and turned the volume to the top and its totally silent
Its only on the phono input that I get the issue.

Thanks, that likely means that the issue is not coming from your speaker leads or from the Naim pre/power (that being so, if you disconnect the Lehmann from the Naim then I would expect that input also to be silent?). Which would logically then indicate the issue is somewhere between the cartridge, through arm, arm-lead to the Lehmann.

Do you have a different interconnect from the Lehmann that you can try? Just a process of elimination.

1 Like

I have a few different interconnects in a box I will give that a try
much obliged sir

I removed the interconnects into Aux 2 and sure enough the channel was silent. I swapped out cables and the problem persists . I don’t have a spare phono stage to hand, so I cannot eliminate the Lehman being at fault but as you say the fault is probably between the cartridge through arm.
The issue becomes apparent at about the 12 o clock position. I will have a chat with my dealer and see if there is a solution beyond sending the arm to SME for a service

Possibly a tuna malfunction?

1 Like

Some of us have had this issue with Linn LP12s in to Naim’s Superline. Simply, the turntable, arm and cabling becomes a radio antenna. With the Superline, the issue can be mitigated by increasing the capacitance via the plugs provided.

Have you had the Lehman long and has this issue just started?

It can sometimes be cured by disconnecting the earth cable (from the TT) and leaving it unconnected or connecting it direct to the Naim pre-amp (assuming there is an earthing connection on it).

I’ve had the Lehman about 6 years and it is a recent issue . I am not sure if there is an earthing connection on the 122x

There appears to be, close to the Aux 2 – marked as ‘Ground’

1 Like

Happy Listener, yes indeed there is. The SME has two ground leads so placed that on the ground and voila problem solved. Thank you very much

3 Likes

In my experience, these issues can also come and go with the weather. All attributed to ‘atmospherics’.

My first Naim based system (CD3.5/102/140) was in our Edwardian house attic conversion. On one occasion it picked up transmissions from our local taxi firm - literally clear as a bell!

1 Like

Otherwise known as “Sunspot activity”. :blush:

I had a problem with my system picking up a radio station when using the phono input. It turned out to be the tonearm phono cables. In my case the one of the cables failed sometime after the problem started, and the tone arm was replaced under warranty. I have not ever had that problem since.

What’s interesting is that I had the problem when I was using my Herron phonostage. I changed from the Herron to the SuperLine and still had the problem. Keith Herron kept telling me the problem was the tonearm phono cable and not interconnects. He was spot on correct.