how,i can extend,the freqency range,of an old analouge lnb,to receive amateur radio?

Turok

Hello!
can someone explain me,what kind of technical stuff is needed,to extend the freqency range,of an old analouge lnb,to receive amateur radio,in the lower freqency range?

here a seller on Ebay,that sells,this kind of lnb now since 3 years,no other can make this ,or sell it too!

item nr!

260468055775

now i want to know what is nesersary,to strecht the lnb freqency range,is there on some lnb,like a scew inside,that i can turn a little bit,i can imagine this,but i think it is much more complicated job to do!
thanks for your input!
good night,from the alps,until tomorrow!

ralphmagno

i do it all the time
when you open the lnb there are 2 frequency screws.
one moves the 9.750 ghz osc the other moved the 10.6 ghz osc.
you must turn the one you want moved counter clock wise this will shift the band about 100 mhz or so .
if you are working with the upper band.
align the dish on german 19 degrees.
find a analog frequency with the 22 khz turned on and twist the screw.
if you do not have a field strength meter with a spectrum analizer
this will be impossible.
this should shift the upper band from 12.750 ghz to about 12.850 or 12.900 ghz.
thats about all you can do.
ralph
how high are you trying to go with the transmission??
what frequency.

the lnb will not be usable anymore with any satellite when you do this because the spectrum has changer and it will not lock on any other satellite.
this will be just for this application.
you would have to move the frequency back to the way it was before.
ralph

Turok

Hello Ralph!
thanks for your reply,i have already this kind of lnb here,but usaly,the use only old lnbs,there where not astra 2d compatible,a Ebay seller told me,the old grundig lnbs are the best to manipulate!
one last questions,how do you close the lnb after opening,that it is waterproof again?

does the manipulation not work on universal lnbs,what is the reason why the use the old analouge lnbs only for this?

Tsiklon

Channel Hopper

The reasons are numerous, but possibly the older style LNBs had a larger oscillator cavity that could be adjusted far further with the screw.

A change from 9.75GHz to 9GHz is a large one, modern LNBs with their cost savings on materials may not have a thread that can be unscrewed far enough, or maybe the stability drops off so much it is unuseable.

There is a very fine line between "hobby" and "mental illness"

nanochickin

Sounds like you need one of the old Sky Analogue bluecap lnbs

I can get my hands on some old Televes Analogue lnbs and some old Channel master Circular polarity lnbs. I'll be decomisioning a load of old systems which use them in the very near future. Both type lnbs have separate feed horns.

theres a piccie of the channel master one, i'll have to dig the Televes ones out


No idea how good they are as they have been up for a few years, although i will try and test them first.

If you think they may be any use to you you can have them for free, although a contribution to the postage would be welcome



Nano

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Turok

have one real massive here,from philiphs,with 2,5 gb noice,i think thats realy old

Channel Hopper

I still have a couple of NEC units (Low noise converters then ) with N type connectors from 1987 ish, 2.5dB in those days would have been optimistic.

There is a very fine line between "hobby" and "mental illness"

Turok

Hello!
my chapparal sban lnb,from the year 1992 has also this kind of big ntype connecotors,looks like an american standart!
in past was posible to receive analouge radio in sband with old stb,but now the switch it all off i think here in europe,never try it again!