Dorpmuller
Member
For my own weird reasons, I'm looking for the I.F. freq of this unit... anyone know it?
Thanks,
Rich
Thanks,
Rich
BCT-7-anyone know the I.F.?
- Thread starter Dorpmuller
- Start date
- Status
wesct
Member
Dorpmuller said:
10.8 mhz
wesct
Anyone have the IF's for the 330T?
I'm having issues with breakthrough/intermod from VHF air to UHF air.
It manifests itself around 309MHz. If I can work out which freqs are coming through I can do something about it (barring just a filter for anything below mil-air)
I'm having issues with breakthrough/intermod from VHF air to UHF air.
It manifests itself around 309MHz. If I can work out which freqs are coming through I can do something about it (barring just a filter for anything below mil-air)
Three ways I can think of that would probably tell you the IF.
1) Open the radio and look for a crystal w/ a 10.? # on it (at least in the old radios, not sure about new ones).
2) Get a STRONG frequency, like police dispatch or a business or something, open the squelch all the way, and search in the range of about 20 - 22 MHz above the freq. For example, PD dispatch is 152.000. I believe common IFs are 10.4, 10.7, and 10.8. Double the IF so it could be 20.8 to 21.6. Now add that range to the dispatch freq of 152.000 and you get the range of 172.8 to 173.6. Search that range with an open squelch (w/ another scanner listening to the correct freq so you can hear when there is activity). You should be able to hear the image.
3) Look in the back of the manual or download the PDF manual. It may say in the specifications what the IF is.
1) Open the radio and look for a crystal w/ a 10.? # on it (at least in the old radios, not sure about new ones).
2) Get a STRONG frequency, like police dispatch or a business or something, open the squelch all the way, and search in the range of about 20 - 22 MHz above the freq. For example, PD dispatch is 152.000. I believe common IFs are 10.4, 10.7, and 10.8. Double the IF so it could be 20.8 to 21.6. Now add that range to the dispatch freq of 152.000 and you get the range of 172.8 to 173.6. Search that range with an open squelch (w/ another scanner listening to the correct freq so you can hear when there is activity). You should be able to hear the image.
3) Look in the back of the manual or download the PDF manual. It may say in the specifications what the IF is.
1 - not an option.
2 - bit hit and miss
3 - tried it, nothing in the manual.
There are three IF's, since its triple conversion, right?
2 - bit hit and miss
3 - tried it, nothing in the manual.
There are three IF's, since its triple conversion, right?
miller
Member
I've received IMD from 139MHz taxi dispatch freq to another freq up 42.6MHz. So maybe 21.3MHz is one of IF for BR330T. Hope this helps! And http://myweb.accessus.net/~090/bc-780xlt.html#interfere shows 3 IFs of BC780XLT can give you some clue!
It only happens around 309MHz. The IMD comes from the VHF airband, as I can just about recognise the comms.
I would guess at 130MHz being the area the breathrough is coming from.
I would guess at 130MHz being the area the breathrough is coming from.
- Status
Similar threads
