[Icom] Re: IC756Pro - mic and cosmetics?

[Chris BONDE]

George:
I think that you are the first to mention that the vent at the top is 
intake rather than exhaust.  To me that is rather a poor design, since heat 
tends to raise.  I have placed my sweaty palm above the vent and thought 
that the air was moving up out of the vent.  Even when I Tx the sensation 
was the same.  However, I took your advice and tried the Keelex text.

I used a virgin piece of Kleenx, placed it very carefully  over the vent, 
it just sat there.  Turned on Tx, still just sat there.  A ha, I was 
right.  But to be fair, I took the extra portion off the tissue so that it 
was only single ply.  (Now everyone knows what single ply does when you 
blow into it.  It opens a very nice hole from whence everything 
eminates!!)  Further, I made the size of the single py tissue the same size 
of the vent, carefully placed it over the vent and obseved.  IT DID NOT 
MOVE.  Watched again.  A ha, the tissue moved up.  Then I turned the TX 
on.  Chagrin!!  The tissue moved down into the vent.  Oh, just an 
aberation, do it again.  So I did, and so I did and so I did.

Yes, I believe that you are correct. The fan sucks the air down through the 
top vent, the vent with the hottest part closest to it, the top vent.  I, 
in my dazed understanding of convection do not understand why such would be 
so designed.  So, alas and alack, I shall go back to my design board (where 
is it?) and see if I can place the fan on the back of the rig.  Hey, that 
would be better!!  It would be out of sight and I could put my log book on 
top of the rig. ( <:+)}  )

Chris opr VE7HCB



At 11:11 PM 2002-04-27 -0500, you wrote:
>Chris, unless I am mistaken, the front top opening is not a vent, it is the
>intake for the internal fan. Heated air is exhausted out the back of the
>rig after passing through the PA compartment, etc. With the fan running lay
>a small bit of Kleenex or whatever on the opening and note that air is
>moving IN and not being exhausted out.
>
>Maybe I have it wrong, but that has been my observation. I can't ever
>recall feeling heated air coming OUT of the top opening.
>
>73/72/oo, George W5YR - the Yellow Rose of Texas
>Fairview, TX 30 mi NE of Dallas in Collin county EM13qe
>Amateur Radio W5YR, in the 56th year and it just keeps getting better!
>QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
>Icom IC-756PRO #02121  Kachina 505 DSP  #91900556  Icom IC-765 #02437