crystal question

Sorry if I'm missing something very obvious here.
Am I wrong in my understanding that one can "simply" swap crystals in the
radio and "all should work"? I recently purchased a replacement receiver (Futaba) and I'm not getting any reception with my old crystal. Any information would be appreciated.
Thanks,
Shai
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Shai wrote:

Ypu can up tpo a point swap crystals in the RECEIVER to chjange channels, tho a re-tune of a couple of coils is advised if you move too far from where it was originally set up.
The same IS true of a transmitter, except you are legally discouraged from doing it.
If you don't know what you are doing, take the rig into the LHS.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Shai, A few other thoughts as well..
1) did you change transmitter frequency also? or just the new receiver? If you changed transmitter frequency, your transmitter may not be "hitting" on the right channel clearly enough for your receiver to read. You can do a search here for pages upon pages of arguments about changing transmitter frequency in the US by changing crystals without retuning, but anyway, Futaba and the FCC recommend you have it retuned. 2) do the 2 receivers use the same crystal TYPE? be sure you have the right crystal type, not a short crystal for a standard crystal application, single conversion in a dual conversion receiver, etc. 3) try purchasing a new crystal and try the new receiver. Still no reception?
hope this helps!
Sincerely, AnnMarie Cross President Crosswinds Equine Rescue, Inc http://hometown.aol.com/horses5ormore/homepage.html
snipped-for-privacy@cs.com (Sport_Pilot) wrote in message

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hi AnnMarie,
Welcome back! Hope the new business is going well.
Don

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hi AnnMarie! Maybe you could answer a question for me. I have a set of 72-7 Futaba crystals. Are these the 'short' single conversion crystals? My DC crystals all seem to be marked 72-10? Thanks!
Jim

in the

receiver
too
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Same brand but perhaps a dual conversion receiver instead of a single conversion receiver? You possibly need a new crystal which is cut to a different specification than the old RX crystal but operates your new RX on the same channel as your TX.. AM, Single conversion AM and earlier PCM all took the same crystal made .455 MHz from listed frequency as the components on the board of the RX made up the difference. Dual Conversion FM (PPM) and PCM receivers have recently become more numerous and they have one or more crystal(s) hard mounted inside the case. The removable crystal is made with only 10.7 MHz difference to the "frequency'. If your old crystal worked in a single conversion receiver, it will not work in a Dual conversion receiver and vice versa. Check your receiver model type at http://www.futaba-rc.com/radioaccys/futl26.html regards Alan T. Alan's Hobby, Model & RC Web Links http://homepages.ihug.co.nz/~atong / ..............................................................

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The question is, why did you buy the replacement receiver? Was the original in a crash? You may have damaged the crystal in the crash as well.
If you're replacing a crashed/failed receiver, get a new crystal too.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.