X-treme eSSB Audio FORUM

Hi all,

I'm Allan, 31 years old and live in france ( center france, JN16RF )

I'm new on this forum and thanks for accepting me here. I'm novice in hifi ssb and have some questions.

My shack use a ts-850+dsp100 ( no mods ) + mic. Apex435. A behringer rack connect like this : mic2200-fbq1502-ex3200-mdx2600-dsp2024, use only left channel by jack connector and go to the 850 front microphone connector.

First question : I don't have a ibox because I don't really understand his function ( my english is not good sorry ) so thanks to someone who can explain me easily. If I need one when I can find a schema for build one. Many thanks.

Second question : I think i have find my settings for my equipment but normaly the ts850 push about 80 watts output power and now with hifi rack, the power go down to about 50 watts. Is it normal ?

That's all for the moment and a big thanks for any help. Thanks for reading me too.

Regards at all,

Allan

Howdy Allan,
Welcome to the Forum!!!
So glad that you are here.

Sounds like you have some great equipment to have lots of Fun!

The Ibox does 2 things for you.

1- It is used as an attenuator, which will bring the Signal level of the Rack equipment (Line Level) down to the level needed for input into the Mic Jack (Mic Level) on the front of the radio. The Rack equipment level is too high to try and input into the Mic jack. Usually when this is done without an attenuator, you will not have the correct control of the Mic Audio. If the Gain levels in the rack equipment are at the correct value, then this will make the gain too high for input into the Front Mic Jack and the Transmit Audio will be too 'Hot'. In order to get the Mic Audio down far enough without the use of an attenuator, you would have to lower the gain in the Rack Equipment and you will loose the Signal to Noise ratio not to mention not really having any control over the Mic Gain.

2- It is used as an isolation transformer. This means that the physical electrical connection is separated from the rack and the 850, but the audio can still pass thru. This is done thru the use of an isolation transformer. This keeps hum, and also RFI from getting into your audio.

For more information on this subject, see John, NU9N's website here:
http://www.nu9n.com/tx.html
Scroll down the page to see the section on transformers and attenuators.

The power output being reduced is typical with using full range Hifi Audio for transmit. This is because that most of the energy used by the radio to develop power is in the mid range audio frequencies and these are normally cut when balancing out your audio for HiFi, along with increasing the lows and highs. Once the ALC is set correctly, meaning minimal to NO ALC on voice peaks, then you may find the power output to be somewhat reduced. We think the majority of the Power Output problem you are having will be somewhat rectified by addressing the problem above with the attenuator.

Also be sure you are using a TRUE Peak reading meter and not going by the Meter on the TS-850 as this is not a true peak reading meter.

Good Luck and Have Fun!!!

Hi Sir,

Many thanks for your reply and for your help.

Ok for the attenuator, first I will made the simple attenuation ( H pad ) because i think i have some resistors here and i will see for an audio isolation transformer for build a ibox ( but here compoment are not easy to finf, i will search on the net ) .

i will came back future with my opinion, also I wait for a deq 1024 and when all was setting Iwill put here my settings.

Many thanks again,

Regards

Allan