[Top] [All Lists]

[TenTec] 1. Adding external line-level amplifiers to Orion 565 AUXIN/OUT

To: tentec@contesting.com
Subject: [TenTec] 1. Adding external line-level amplifiers to Orion 565 AUXIN/OUT 2. Adding Stereo Speakers to Orion 565 3. Making your own AUXbreakout box
From: Jerry Volpe <kg6tt@arrl.net>
Reply-to: kg6tt@arrl.net,Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Wed, 19 Dec 2007 02:57:49 -0800
List-post: <mailto:tentec@contesting.com>
1. Dealing with decreased AUX gain (in and out)in the Orion 565 under 
Firmware 2.62a.

One of the unexpected consequences of Firmware 2.62A is a noticeable 
drop in the fixed audio level of the AUX Left and Right outputs (yes, 
both audio channels are available on the Orion's AUX connector, although 
the cable Ten-Tec provides doesn't give either the Right audio output or 
the FSK input signals so you need to buy or build your own breakout 
cable/box to get to these signals.... see 3. below) as well as reduced 
sensitivity on the AUX audio input. Depending on your applications this 
may or may not be an issue to you. Unfortunately it was to me, but not 
one that didn't have a work around.

My major 'audio level' issue involved my sound card applications (PSK31 
for example). My station computers all use Delta 44 sound cards which 
have excellent signal-to-noise, dynamic range, etc.. but also have lower 
gain on their inputs and outputs than what I experience with typical 
consumer add-on sound cards or those built into most motherboards. 
Anyway, when I switched to Firmware 2.62A the Orion's AUX outs and 
Inputs were no longer signal compatible with the Delta sound card. I 
sent off several appeals to Ten-Tec regarding this but to date (months 
later) I haven't received any acknowledgment of this... so while I wait 
I decided to boost the audio out of and into the AUX connector myself. 
Fortunately I discovered some neat 'off the shelf' products that served 
my needs and took up practically no shack space.

Radio Design Labs (RDL) produces an incredible diverse line of products 
for use in a multitude of audio applications (studio, general purpose 
PA, radio station, etc.) Many of these are packaged as 'stick ups' in 
unusually small black plastic encased packages designed to be literally 
stuck where needed using velcro or double-sided sticky tape!. They have 
numerous configurations of small audio amplifiers just perfect to 
increase the output of the AUX Left and Right audio signals and to boost 
the sensitivity of the AUX audio input line.... all to levels more 
appropriate for professional sound card and other devices that the 
Firmware version 2.62A Orion can't supply. The new stock prices of the 
RDL modules can be a bit pricey... fortunately I found that they show up 
on auction sites rather frequently and at really nice buynow discounts. 
I added a small independently channel adjustable stereo 'headphone' 
amplifier module (about 1 1/2 x 1/2 x 2 1/2 inches in size) on the 
Orion's AUX Left and Right audio outputs and a small single-channel 
line-level audio amp module on the Orion's AUX audio input. It seems 
that all RDL modules run on 24 VDC so I had to get a couple of 
appropriate 24 VDC power cubes. I use small guage RG-176U on all RDL 
module inputs and outputs (with multi-wrapped ferrites on each). The 
results are great and as they are fully level adjustable I am ready for 
the next Orion firmware update. I paid $15 for one module and $35 for 
the other... one was NOS the other NEW.

2. Accessing both Right and Left audio outputs - amplifying to speaker 
output level.

Personally I tend to use stereo earphones with my Orion... helps dig out 
weak signals but also allows me to take full advantage of the second 
receiver and Binaural audio (cool... thanks Ten-Tec).... however there 
are times when I'd prefer to sit back without my head encased in mini 
speakers but still be able to aurally separate the MAIN and SUB 
receivers..... and use Binaural too! All you have to do is get at the 
AUX Audio Right and Left signals which requires some sort of 'breakout' 
box or cable.

Now the AUX Left and Right audio levels are 'fixed'... they don't vary 
with the front panel Volume controls. So whatever external audio 
amplifier I used had to have sufficient gain and be adjustable (with 
some sort of balance control too).... and be cheap... and be RF 
insensitive! What do you know... RDL to the rescue once again. One day 
an automatic alert I had set on an auction site notified me that there 
was a listing for a Radio Design Labs audio amplifier. I checked it out 
and it was perfect for what I needed. Small... separate volume controls 
for Left and Right... over 4 watts of CLEAN audio per channel. I spent a 
quick $35 plus shipping and then when searching for a larger 24 VDC 
power module (at least 1amp). Found one. A few days later everything was 
at the shack and ready for installation.... all I had to do was add two 
vintage Radio Shack Minimus 11 dye cast aluminum speakers and the end 
results were far more pleasing than what I had anticipated. Before 
adding the external amplifier I had been using a SoundSweet speaker on 
the Orion and very pleased other than not being able to tap into the 
stereo and binaural features without using headphones. Now with my new 
'optional' stereo in the shack I have the best of both worlds. Not for 
everybody, but who knows.

3. Using a home-brew (or commercial) breakout box to obtain ALL signals 
on the AUX connector.

The Orion's rear panel AUX connector has both the LEFT and RIGHT audio 
signals (as well as FSK!), but as already mentioned the audio breakout 
cable Ten-Tec provides only has the LEFT audio signal. Hmmmmmmmm. LDG 
has a cool breakout box product that plugs into the AUX connector and 
gives RCA connections to all of the AUX signals. That LDG product is a 
bit pricey (about $70) so I decided to build my own. A quick look at the 
Buxcomm website showed a pre-wired eight-pin DIN connector/cable (just 
remember your resistor color codes and you will know that wire goes to 
what pin) for under $10. That with some RCA jacks and small plastic 
project box and a ferrite (love those) provide a full breakout box for 
the Orion for under $20.


What I used:

1. Radio Design Labs ST-DA3 Audio Distribution Amplifier to boost audio 
signals from Delta sound card to Orion's AUX Audio Input.
2. Radio Design Labs RU-PA518 Audio Power Amplifier for the stereo, room 
filling, speaker level output.
3. Valcom VP-1124, 24VDC, 1A Receptacle Mount Power Supply.
4. Radio Design Labs ST-SH1 Stereo Headphone amplifier
5. Pair of old Radio Shack Minimus 11 speakers.


Hope this is useful to someone.... and pardon the typos as it is 3am and 
that is what happens. :)

Jerry, KG6TT

Ralph Jerald "Jerry" Volpe
Amateur Radio Operator KG6TT
FISTS 12304
788 Chestnut Drive
Fairfield, CA 94533


510 325-7724
707 399-8838 FAX

TenTec mailing list

<Prev in Thread] Current Thread [Next in Thread>
  • [TenTec] 1. Adding external line-level amplifiers to Orion 565 AUXIN/OUT 2. Adding Stereo Speakers to Orion 565 3. Making your own AUXbreakout box, Jerry Volpe <=