radio display

How to keep the Cessna 170 flying and airworthy.

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simatos
Posts: 108
Joined: Tue Sep 07, 2004 9:31 pm

radio display

Post by simatos »

I wonder if any of you might help with a radio issue. I have a Bendix King Radio model 97 or 197 14volt new outta the box powered up last week. works OK except the display is very pale for lack of a better description. If you look at a certain angle the frequency numbers practically dissappear. I have a panel light dimmer which has no effect on the intensity of the display. Of course the owners manual is with my avionics guy whoo is not answering the phone. Any ideas???????Is there an intensity adjustment somewhere on this radio. Not directly 170 related but this is a common radio I hope some of you might have some ideas Thanks Gary
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GAHorn
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Post by GAHorn »

Some of them have photo-cells that dim them in the dark. Perhaps yours is dimmed?
Or.... are you viewing it in bright sunlight? Many of that type are only capable of handling just so much direct sunlight.
Finally, if it's not a new unit, it may be in trouble. The displays can be relatively expensive to replace, but can certainly be done by any qualified avionics shop. The KY-97 is a good unit.

Hope this helps.

PS - I viewed a KY97 online, and now it seems that my memory seems to tell me the photo-cell is to the right of the display. The max-brilliance of the display can indeed be adjusted by an avionics shop (within the capability of the unit and dependent upon the unit's health.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
spiro
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Post by spiro »

look at your install manual, there's at least a couple ways to wire them up. The "standard" way is to connect to the panel dimmer circuit so the radio lighting follows the panel lights. When wired this way the radio goes to ½ intensity when the panel lights are off. It sounds like yours is wired for ½ intensity all the time.

I found that ½ intensity not bright enuf to see in daylight with the radio down in the lower left corner of my panel so I wired mine for full brightness all the time. Not a problem, even on the darkest of nights.

I'm not aware of any photocell on a KY-97A.

- paul
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GAHorn
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Post by GAHorn »

Another thought on this subject, simatos,... the KY 97 and 97A are LCD displays. In that case, there will be less definition in the display because all one can do with LCD displays is either back-light them. Backlighting is only effective in dark environs such as at night.
The KY-197 and 197A are essentially the same radio, but they have gas discharge displays which are VERY much brighter.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
spiro
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Post by spiro »

gahorn wrote: the KY 97 and 97A are LCD displays. .... The KY-197 and 197A are essentially the same radio, but they have gas discharge displays
the 97 is a 5 watt radio, the 197 is a 10 watt
simatos
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Joined: Tue Sep 07, 2004 9:31 pm

Post by simatos »

Guys Thanks. I did review the possibility of permantly wiring the radio to give half the intensity of the display and I don't think that is the case. I guess I will have to locate the manual and go over it carefully. The unit does have a little eye on the front likely a photo detector but when covered it still did not bring up the intensity. Like they say when all else fails read the manual. Again as a new unit my hope is it is a set - up or adjust issue. I will let you know what I find and thank you all very much for you adviceG
PilotMikeTX
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Post by PilotMikeTX »

I'm pretty sure the photo detector eye should dim the display when covered and brighten it when you shine a light at it.
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GAHorn
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Post by GAHorn »

spiro wrote:
gahorn wrote: the KY 97 and 97A are LCD displays. .... The KY-197 and 197A are essentially the same radio, but they have gas discharge displays
the 97 is a 5 watt radio, the 197 is a 10 watt
Yes, correct. Thanks Spiro, but I didn't consider that germaine to the complaint. Sorry if I mislead anyone. (The higher wattage transmitters are suggested if installing in a jet or high-altitude operation in order to better insure long-range communication. I doubt it's an issue in a 170.) My primary intent was to point out the difference between an LCD and a Gas Discharge display.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
simatos
Posts: 108
Joined: Tue Sep 07, 2004 9:31 pm

Post by simatos »

Still tearing my hair out re low intensity of display and inability to locat install diagram. Just sent Spiro email but perhaps others my be able to help. I have just yanked the radio out and when you look at the back you have a contact bar with 15 contacts on the upper surface and another 15 contacts on the lower surface. One of these is supposed to stay open/unconnected to allow the full intensity of the display?? Any ideas. Could I put tape over one contact at a time and reinstall and locate it that way or is there a risk of cooking the radio????????????
Signed Frustrated in Pitt Meadows
(simatos)
Mabe my next airplane should be something simple like the Space Shuttle
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GAHorn
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Post by GAHorn »

simatos, you'd be far better off to simply consult with a genuine avionics shop/dealer than to risk injuring the radio and/or violating the warranty. Contact one of the may shops available online and ask them about it. IMHO
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
spiro
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Joined: Mon Jan 27, 2003 11:08 am

Post by spiro »

no need for this to be private, it's a forum so all can benefit:
simatos wrote:.... my avionic guys can't locate the install documents. .... can you tell me how you wired yours up to give the full intensity display??
firstly, I'd get a new avionics guy...

looking at the connector from the front of the rack, the contacts on the top are labeled
A B C D E F H J K L M N P R S
from left to right
and the lower contacts are 1 thru 15, again left to right.
the polarizing key is between J & K, 8 & 9.

R & 14 are Aircraft Power +13.75 VDC in
P & 13 are Switched Aircraft Power out
M & 11 are +13.75 VDC Power in
B is +14 VDC Lighting Hi
1 is Lighting Lo, and
A is Dim Select

P/13 and M/11 should be jumpered together.

"For tracking of a 14V lighting bus, leave Dim Select (Pin A) unconnected. When panel dimmer is turned all the way down backlighting goes to half brightness. If continous half brightness is desired Pin A can be connected to aircraft supply. If no connection is made to the aircraft dimmer bus and Dim Select, the backlighting will be at half brightness."

sounds like you've either got A connected to power, or A and B both disconnected. If you want it to follow the panel dimmer connect B to the dimmer circuit and leave A unconnected. Mine are wired for full brightness whenever the radio's turned on; B is connected to P/13/M/11.

I'm an engineer and A&P, not an avionics tech. Like Bruce is fond of saying, this post is worth what you paid for it.

- paul
zero.one.victor
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Post by zero.one.victor »

Gary, I didn't know you were based at Pitt Meadows. Did Al Tice up there ever sell his 180-horse B model? I flew up and looked at it last April, and we flew in it over to Chilliwack for lunch. I ended up deciding not to buy it, but it seemed like a pretty good airplane. Hope Al's doing well, he seemed like a nice guy.

Eric
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GAHorn
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Post by GAHorn »

OK, Simatos. Here's a quck way to get the pinouts and the installation manual for your radio. They will email or fax it to you for a small feel.
http://www.avionix.com/manuals.html

(Whew! I just KNEW this was available somewhere.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
CraigH
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Joined: Wed Aug 31, 2005 11:55 pm

Post by CraigH »

gahorn wrote:OK, Simatos. Here's a quck way to get the pinouts and the installation manual for your radio. They will email or fax it to you for a small feel.
http://www.avionix.com/manuals.html

(Whew! I just KNEW this was available somewhere.)
I wouldn't mind paying a small fee, but a small FEEL seems just a little bit too personal. :oops: :lol:
Craig Helm
Graham, TX (KRPH)
2000 RV-4
ex-owner 1956 Cessna 170B N3477D, now CF-DLR
doug8082a
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Post by doug8082a »

CraigH wrote:
gahorn wrote:OK, Simatos. Here's a quck way to get the pinouts and the installation manual for your radio. They will email or fax it to you for a small feel.
http://www.avionix.com/manuals.html

(Whew! I just KNEW this was available somewhere.)
I wouldn't mind paying a small fee, but a small FEEL seems just a little bit too personal. :oops: :lol:
I wonder what George had to go through to get this information in the first place... 8O :P :oops:
Doug
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