Most likely, You were generating too much power. Also the cellular transmitter wasn't transmitting in the right spots or transmitting at all. Also the phone could of interpreted the mixer and modulator as a high VSWR source and shut off that way
I found out today that I have was a custom designed "Level 7" mixer, which means the LO it wants to see is +7dBm or 5 milliwatts. A cellular bag phone typically produces 3 watts which is about +34.5dB, you may of cooked the mixer. Also the power attenuation pads should be removed from the modulator, the closer you can get that to +0 (1mW) the better. I would open the phone and find the RF signal before it hits the final power brick and use that, it should be in the 20-50mW range. Unfortunately my mixer is only rated to 1GHz. So I am not sure if it will work for me or not. I am using a Larcan-TTC P369 modulator with the dip switches fliped to output on Cable frequencys, Ch.33 = 277.25 MHz. I have yet to build the LO chain but it will generate 1GHz in the +7 to +13dB range. I have built the amplifier, but awaiting test equipment before I can tell you how much it puts out. I am using the Mitsubishi RA18H1213G, Special care must be used with this brick as it needs its heatsink machined to perfect flatness other wise it will destroy itself. I expect 25-30 watts output for 20mW input. Reciever is a Semi modified Cadco 375 tuned to CH.59 = 433.25 and rubbered up to 434.0 Playing with building the filters today. For the recieve side I am using a 7 pole interdigital BPF with 5.6MHz of bandwidth constructed from all aluminum, and a 6 pole with similar specs for the transmitter. On Thu, 10 Feb 2005 11:58:57 -0800 (PST), Benjamin Naber <[EMAIL PROTECTED]> wrote: > > I'd like to know more about what you are doing > > I have a MCL mixer and attempted the same thing, but > using a cell phone in test mode (848.25MHz) as the LO > and a video modulator that outputs on channel 3 > (61.75MHz?)for the IF. This was to achieve a 910MHz RF > out from the mixer. > > It didn't work and I wonder if I was putting too much > power into the mixer from the cell phone - but I am > not sure because the cell phone turned off after I > connected the phone to the mixer and turned on the > transmitter... perhaps I need and attenuator pad of > 3dB or better... > > ~Ben, KB9LFZ > > --- DCFluX <[EMAIL PROTECTED]> wrote: > > > > > I have a Circa 1982 Mini Circuits mixer, ZXM-2 but > > it seems it is not > > made anymore as MCL denies all knowledge of its > > existince. I was > > wondering if anyone had the spec sheet for it? It > > has three BNC > > connectors on in, "R" "I" "L" and is about 2" X > > 3/4". I was hoping I > > could run a 1GHz LO into it to hetrodyne a cable > > modulator to 1277.25 > > for my up and coming ATV repeater project. > > > > > > > > > > > > Yahoo! Groups Links > > > > > > [EMAIL PROTECTED] > > > > > > > > > > > > > > ===== > ------------------------------------------------- > ~Ben, KB9LFZ > > Got your radio on and "listening?" > Then KEY the radio and say that you are! LET US USE WHAT WE HAVE!! > > > __________________________________ > Do you Yahoo!? > Yahoo! Mail - Helps protect you from nasty viruses. > http://promotions.yahoo.com/new_mail > > Yahoo! Groups Links > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
