Any ideas?

[kai]

The cables look like ancient 7/029 ring conductors, how old was the installation? - it could have dated from the Cold War perhaps???

 

[electronicsuk]

Well, I'd certainly be freaked if I found that in my house. Presumably there must be something there that can be dated to get a vague idea of how long it might have been there for?

 

[bernardgreen]

The marking on the electrolytic capacitor ( the large black component ) may have a date code and that will give the earliest date the bug could have been built. Other components might also have readable date codes.

But in view of the illegality of using this device and the possible dubious reason it was installed an in depth investigation by amateurs may create problems for those involved.

 

[comms]

I'd be checking the ceiling for small holes & the RG59 running to a recorder.

 

[sjwkmje]

The cables look like ancient 7/029 ring conductors, how old was the installation? - it could have dated from the Cold War perhaps???

Not even possible.

Looking at the PCBs you have 0605 SMD style resistors and 0805 SMD style capacitors and a new style looking inductor. Couple that with the diodes on the power supply the PCB with the big electrolytic capacitor (looks like its for decoupling / smoothing purposes) and the quite modern looking 1% metal film resistor I say less than 5 years or so.

You could apply f = 1 / 2 pi sqrt LC to give you the frequency it is transmitting at as you can see the capacitors and then the inductor so it could be parallel or series combination but looking closer I am going with a single RF stage one transistor and one transistor for a preamp for the mic. You can see what looks like SMD transistors on that second board.

Good find. It would not be to hard for some one to nock this up. We did a couple of designs in college as a proof of concept using a two stage design and a single inductor / parallel capacitor network during comms theory. Its basic electronics transistors tunned circuits etc. Nothing professional about it at all.

Adam

 

[RF Lighting]

The cables were 6.0mm² t&e.

Apparently it looked like the socket had been wired later than the rest of the installation, so may have been out in specifically for this bug.

I will see if I can get hold of the offending item at some point.

My mates apprentice has powered it up and used a scanner to find the frequency, so I'll try and find this out and let you know.

 

[BS3036]

and used a scanner to find the frequency

My estimate is somewhere in the FM broadcast band. So - between 88MHz and 108MHz.

 

[holmslaw]

..

 

[Chri5]

and used a scanner to find the frequency

My estimate is somewhere in the FM broadcast band. So - between 88MHz and 108MHz.

100% likely.

Let's not get carried away with this, the bug is likely to have been a neurotic husband of the last owners. Was the lady of the house known or renown as a lady of pleasure and leisure

In the 80's comms world I knew of a Co's sales force that were issue with bug pens to 'ease' the sales process. they would leave a note book and pen in the board room under the pretext of the directors needing to discuss the sale.
They'd be outside with a FM radio and head phone listen to the figure the FD would be suggesting as a 'yes' to the sale.

Hence they'd return to the room and have 100% understanding of the clients green light positioning.

 

[tim west]

wonder if it was wired in s pyro?

 

[mo2]

gawd find out the history
and it would help if you took the components off it for closer inspection