Why would Talksport be heard on approx 170kHz??

['LIVEWIRE?']

Obviously an image frequency created in the receiver (a Romanian made Replica Philips 'Ovaltiney' radio, since you ask!!), but, as 1053Khz is normally the strongest of their two main frequencies in this area, I can't work out how this station appears where it does on LW. With an I.F. of 460kHz, a radio tuned to 133kHz might pick up T.S., but not one tuned to 185! T.S's other main frequency (1089kHz) is weaker in these parts, and it's image would fall below the LW band anyway (It could be a 2nd. harmonic of the L.O. freq. if the radio was set to 169kHz - the dial calibration on this radio is 100% accurate!)

[turretslug]

The 2nd harmonic suggestion sounds quite plausible- local oscillators can be quite mucky as regards harmonics and all sorts of oddities can be unexpectedly tuned if the front-end is a bit "open" as regards selectivity and/or screening! The sort of simple tranny with aerial straight into self-oscillating mixer always seems to be prone to this sort of thing, notoriously I recall a Perdio "Town and Country" (LW, MW, Trawler Band) set that was positively swimming with whistles and spurious responses, with MW stations in that normally quiet upper LW region and legions of SW stations across TB. Perhaps the normal wide spread of transistor characteristics results in the occasional mix/osc stage that ends up going a bit mad. One of the reasons I classify "proper" radios as ones with an RF stage and separate oscillator (even if just triode-hexode), it seems to be a step towards keeping things "clean".

I once had a Philips portable that would clearly tune in TV sound carriers across the top of its VHF/FM band and attributed this to oscillator harmonics and a "loose" front end.

[terrykc]

There is a snag to the calculations you are making. The local oscillator is normally above the signal frequency, not below it!

We sometimes used to temporarily tack a spare MW ferrite rod aerial across a sets own MW coil and use the set to tune into the local old boy's daily morning net on Top Band! (Using a ferrite rod aerial meant it was easy to peak it up rather than twiddling a core.)

I don't recall one of those Perdio sets with Trawler Band. They probably did the same as us!

You can prove this by getting another radio - ideally with a ferrite rod aerial - and stand it right next to the other one tuned to 1053kHz. You should be able to tune in to its LO on 1513kHz (198m).

[Nuvistor]

Are there any stations on or near 1223khz or 883khz, if so one of those could be mixing with 1053khz to give 170khz.

[ms660]

Ref Post#1, 1089kHz minus IFx2 (920kHz) = 169kHz...170kHz in the thread title....what does the 185 signify ?

Lawrence.

['LIVEWIRE?']

The 185 was my 'guesstimate' of the frequency to which the radio was tuned, based on it's dial calibration, but I later realized that 170 was nearer the mark, as indeed it was. Now I know that the L.O. in almost all domestic receivers is above the incoming R,F., so, although i didn't think of it, Frank's mention of 883kHz may be right, as BBC R. Wales on 882 is usually a good signal in this area. I can't however work out how a station on either of those frequencies could cause a radio to receive Talksport 1089kHz on 169kHz.

[Nuvistor]

With you saying 1053 was the stronger station for TS I just added and subtracted 170, the mixing could be anywhere not even in the set but more likely is.

[ms660]

Only thing I can think of is image frequency or Luxembourg effect, eg: TS modulating a weak signal on or around 170kHz.

Lawrence.