TMA-MHA tetra - RF Cafe Forums

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tomsk45
Post subject: TMA-MHA tetra Posted: Wed Jul 12, 2006 5:52 pm

Lieutenant

Joined: Wed Jul 12, 2006 5:26 pm
Posts: 3
Where should the values lie? Parameter for the good RX/TX
TMA. RX 380-385, TX 390-395

Noise
OIP3
P1dB
RX Rejection
TX Rejection
Time Delay
Bypass-loss
Insertion-Loss
Intermodulation
Ripple in Rx-band
Gain variation over temperature
Duplexer 70dB for 5MhZ is okay?
Bandpass Ripple
Speed max 350kmh

Tetra 380MHz (25kHz), Power Handling max. 8x45dBm, Gain 15-20dB, BTS Sensity static -119dBm, Mine english is very bad, apology.


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nubbage
Post subject: TMA-MHA tetraPosted: Thu Jul 13, 2006 6:21 am

General


Joined: Fri Feb 17, 2006 12:07 pm
Posts: 218
Location: London UK
Hi Tomsk

Check out specs for eqipment by Tait (of New Zealand), Motorola (who now no longer supply to Europe due to RoHS) and Nokia/EADS

Looking at your list, a main concern would be IP3 products for 8 channels running 45dBm Tx output one one mast. Check out these combos by going thru all possible 2*F2-F1 combinations looking for any IP3 products that fall in the receive part of the band.

Other parameters should drop out of manufacturers specs


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tomsk45
Post subject: Posted: Thu Jul 13, 2006 7:32 am

Lieutenant

Joined: Wed Jul 12, 2006 5:26 pm
Posts: 3
That is not exactly the point, I knows (has) manufacturers of values, and I must have a good TMA. Therefore where the parameters are to lie in sentence by sentence? Me would help also the parameters of Motorola or R&S TMA.

thanks


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tomsk45
Post subject: zolotarev?Posted: Wed Aug 16, 2006 4:29 am

Lieutenant

Joined: Wed Jul 12, 2006 5:26 pm
Posts: 3
would it be better if one by means of the LPZ470 (http://www.profilant.net/uk/combiner/12070500) everything cuts off upward? thank you


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nubbage
Post subject: TMA-MHA tetraPosted: Thu Aug 17, 2006 6:07 am

General


Joined: Fri Feb 17, 2006 12:07 pm
Posts: 218
Location: London UK
You need to consult the TETRA Specifications published by ETSI
They are complicated but contain all the details you requested.



Posted  11/12/2012