Just the frequency. That's the only difference. Look at the crystal formulas - one is +LO and the other is -LO. So, the LO will be running above or below the actual receive frequency.
Joe M. WD7F - John in Tucson wrote: > > Curious as to what is different in the crystal when it is cut for low side > vs high side. > > de WD7F > John in Tucson > > ----- Original Message ----- > From: "Eric Lemmon" <[EMAIL PROTECTED]> > To: <Repeater-Builder@yahoogroups.com> > Cc: <[EMAIL PROTECTED]> > Sent: Monday, January 01, 2007 10:55 AM > Subject: [Repeater-Builder] RE: Bomar Crystals Ordered, all the RX not > working for GE EXEC II mobiles > > Yes, it is a sensitive adjustment. How can an LO crystal not be either high > or low side injection? When you order a receive crystal for a Mastr II or > Exec II radio, you must state whether it will be used for high or low side > injection. > > 73, Eric Lemmon WB6FLY > > -----Original Message----- > From: Repeater-Builder@yahoogroups.com > [mailto:[EMAIL PROTECTED] On Behalf Of Mathew Quaife > Sent: Monday, January 01, 2007 9:31 AM > To: Repeater-Builder@yahoogroups.com > Subject: RE: [Repeater-Builder] Bomar Crystals Ordered, all the RX not > working for GE EXEC II mobiles > > I ordered just the xtals from them. One the UHF version, the crystals that > I had tuned them up are at 434.850, was neither high or low side injection. > The xtal that I put in this radio is at 434.875 MHz with a high side > injection. Could it be that far off. > > Mathew > > Eric Lemmon <[EMAIL PROTECTED]> wrote: > > Mathew, > > Did you order just bare crystals to put in some existing channel > elements, > or did you send the elements to Bomar and have them compensated with > the new > crystals? That may be part of the problem, but usually the lack of > compensation doesn't prevent the crystal from operating- it just > might allow > them to drift more than the specified tolerance. > > Since the Exec II radio has tuning adjustments in both the > oscillator-multiplier and the RF assembly, the non-operation may be > nothing > more than a lack of tuning. If the previous frequencies are far > removed > from the new frequencies, the tuning may be so far off that the > oscillator > is not even working. What channel frequencies were used previously? > > It may be that some components may need to be changed to optimize > the radios > for out-of-band operation. > > 73, Eric Lemmon WB6FLY > > -----Original Message----- > From: Repeater-Builder@yahoogroups.com > <mailto:Repeater-Builder%40yahoogroups.com> > [mailto:Repeater-Builder@yahoogroups.com > <mailto:Repeater-Builder%40yahoogroups.com> ] On Behalf Of Mathew Quaife > Sent: Monday, January 01, 2007 9:09 AM > To: Repeater-Builder@yahoogroups.com > <mailto:Repeater-Builder%40yahoogroups.com> > Subject: Re: [Repeater-Builder] Bowmar Crystals Ordered, all the RX > not > working for GE EXEC II mobiles > > Thanks Chuck, found them in the list that was referenced. So these > are > correct, why do they not work? Anyone with any good ideas? > > Mathew > > Chuck Kelsey <[EMAIL PROTECTED] <mailto:kelsey%40madbbs.com> > > wrote: > > For high side, high band -- F+11.2/9 > > For high side, UHF -- F+11.2/27 > > Chuck > WB2EDV > > ----- Original Message ----- > From: Mathew Quaife <mailto:[EMAIL PROTECTED] <mailto:n9lv%40yahoo.com> > > > To: Repeater-Builder@yahoogroups.com > <mailto:Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder@yahoogroups.com > <mailto:Repeater-Builder%40yahoogroups.com> > > Sent: Monday, January 01, 2007 11:44 AM > Subject: Re: [Repeater-Builder] Bowmar Crystals Ordered, all > the RX not working for GE EXEC II mobiles > > Thanks Chuck, that is what they sent me, so your math is > just fine. Then there must be something I am missing. I can take one > of > the old xtals and they work out just fine, so I know the receivers > are > working. Might I ask what the formula you used was? It's been a long > time > since I have calculated a crystal freq. so just need the formula > configuration. > > Mathew > > Chuck Kelsey <[EMAIL PROTECTED] <mailto:kelsey%40madbbs.com> > > wrote: > > If my hasty math is correct: > > 144.81 low side = 14.845555 > 144.81 high side = 17.334444 > > 434.875 low side = 16.39537 > 434.875 high side = 16.521296 > > Chuck > WB2EDV > > ----- Original Message ----- > From: "n9lv" <[EMAIL PROTECTED] <mailto:n9lv%40yahoo.com> > <mailto:n9lv%40yahoo.com> > > To: <Repeater-Builder@yahoogroups.com > <mailto:Repeater-Builder%40yahoogroups.com> > <mailto:Repeater-Builder%40yahoogroups.com> > > Sent: Monday, January 01, 2007 10:40 AM > Subject: [Repeater-Builder] Bowmar Crystals Ordered, > all the RX not working > for GE EXEC II mobiles > > > Hope someone can help shed some light here. I > ordered xtals from > > Bomar (3 week wait) for the GE EXEC II mobile > radios, 6 for RX for > > 144.810 and one RX of 434.875, all high side > injection. None of them > > are working at all. At the same time I ordered tx > xtals for the same > > radio, they all work just fine. What might I be > missing here, or did > > they just cut them all wrong. > > > > Mathew > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com > > Yahoo! Groups Links > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.1.409 / Virus Database: 268.16.2/613 - Release Date: 1/1/2007 > > > Yahoo! Groups Links > > >
