RADIOS AND TNCS FOR USE IN 9600 BAUD

WINLINK 2000 NETWORKING

 

AUG 24, 2004

 

VHF/UHF PACKET RADIOS - EVALUATED AT 9600 BAUD

(Edited from a table provided by Mike Tracy, KC1SX, ARRL Lab, August 20, 2004)

Radio Model / QST Issue

RX BER

12 dB SINAD

2M / 70 cm

RX BER

16 dB SINAD

2M / 70 cm

RX BER,

–50 dBm

2M / 70 cm

TX BER,

12 dB SINAD

2M / 70 cm

TX BER,

SINAD + 30 dB

2M / 70 cm

ICOM IC-208H

 Oct 2003

9.0 E–5

7.7 E–5

<1.0 E–5

<1.0 E–5

<1.0 E–5

<1.0 E–5

1.3 E–3

4.5 E–4

4.0 E–4

2.4 E–5

Yaesu FT-7800

Apr 2004

1.5 E–3

1.4 E–3

1.4 E–4

1.0 E–4

2.1 E–5

1.7 E–5

4.1 E–3

1.9 E–3

3.5 E–5

<1.0 E–5

Alinco DR-135TP

Jan 2001

5.9 E–4

1.0     E–5

<1.0 E–5

2.4 E–3

8.5 E–5

Alinco DR-235

Nov 2003

3.8 E–3

(223 MHz)

1.4 E–4

(223 MHz)

2.4 E–5

(223 MHz)

2.5 E–3

(223 MHz)

3.4 E–4

(223 MHz)

ICOM IC-910H

May 2001 (3 band)

(1.2G)

7.4 E–4

7.1 E–4

9.4 E­–4

1.1     E–5

1.7 E–5

<1.0 E–5

<1.0 E–5

<1.0 E–5

<1.0 E–5

1.5 E–3

1.6 E–3

1.7 E–3

<1.0 E–5

<1.0 E–5

<1.0 E–5

Kenwood TM-D700A

May 2000 (ext. TNC)

8.3 E–4

6.5 E–4

2.4 E–5

3.0 E–5

<1.0 E–5

<1.0 E–5

1.2 E–3

8.6 E–4

<1.0 E–5

<1.0 E–5

ICOM IC-2720H

Mar 2003 (sep rcvrs)

5.0 E–4

1.0 E–4

<1.0 E–5

<1.0 E–5

<1.0 E–5

<1.0 E–5

4.4 E–3

9.2 E–4

1.0 E–3

2.0 E–4

Kenwood TS-2000

Jul 2001   (hf/vhf/uhf)

7.9 E–5

2.9 E–4

<1.0 E–5

<1.0 E–5

<1.0 E–5

<1.0 E–5

1.7 E–4

1.5 E–4

<1.0 E–5

<1.0 E–5

Icom IC-706 M II G

Jun 1999  (hf/vhf/uhf)

2.2E-3

2.3E-3

4.6E-5

8.4E-5

<1.0E-5

<1.0E-5

4.6E-3

2.8E-3

2.1E-4

1.9E-4

Yaesu FT-817

Apr 2001 (hf/vhf/uhf)

1.7 E–3

1.3 E–3

7.6 E–5

7.2 E–5

<1.0 E–5

<1.0 E–5

7.7 E–4

7.5 E–4

<1.0 E–5

<1.0 E–5

Yaesu FT-857

Aug 2003 (hf/vhf/uhf)

2.8 E–3

3.3 E–3

1.4 E–4

1.5 E–4

<1.0 E–5

<1.0 E–5

7.7 E–4

8.3 E–4

<1.0 E–5

<1.0 E–5

Yaesu FT-897

May 2003 (hf/vhf/uhf)

1.7 E–3

2.3 E–3

7.0 E–5

8.0 E–5

<1.0 E–5

<1.0 E–5

1.0 E–3

8.0 E–4

<1.0 E–5

<1.0 E–5

Yaesu FT-7100M

Aug 2001

2.5 E–3

1.9 E–3

5.6 E–4

2.5 E–4

1.6 E–4

8.2 E–5

2.0 E–2

3.4 E–2

1.4 E–2 (see

1.7 E–2  review)

Yaesu FT-1500

Jul 2000

2.5 E–3

4.4 E–5

1.4 E–5

9.3 E–3

3.0 E–4

(see note 1)

 

Notes:

1. The Yaesu FT-1500 is not really suitable for a packet backbone system because the PLL has a key-down instability problem (insufficient settling time allowed before RF output) that can cause problems with nearby repeater systems.

 

2. RX data in red suggests marginal throughput conditions or failure with long packets. Tests conducted with external lab TNC.

 

3. The Bit Error Rate (BER) is the ratio of the number of bits handled in error to the total number of bits transmitted or received in a given test. Thus a BER of 1 E-3 indicates that one out of a thousand bits is likely to fail to pass error free out of 1000 sent. When sending packets of 255 bytes each, this would suggest every packet would contain at least one bit error causing the packet to be rejected. Sufficient safety margin in the radio link should exist to ensure minimal rejected packets in order to maintain the data throughput. Radio FSK performance at 9600 baud degrades as noise becomes present in the recovered received data as well as from bandpass filter effects at low signal levels. Error rates also depend upon the method used to balance the transmitted bit format in the originating TNC as well as the recovery format used in the receiving TNC. At 9600 baud data rate the bits are not handled sequentially with audio frequency shift keying as done in 1200 baud applications.

 

For more information regarding Bit Error Rate testing and radio evaluation see the QST article “‘9600-Ready’ Radios: Ready or Not?” Jon Bloom, KE3Z, ARRL Senior Engineer, May 1995 QST Volume 79, Number 5, available via the search engine on http://www.arrl.org, members only.



TNCs RECOMMENDED FOR 9600 BAUD OPERATION

 

A number of new radios with built-in TNCs have limited buffer size and/or limited computer COM port speed capabilities which may hinder operation on Winlink 2000 or other applications requiring packet lengths greater than 128 bytes at 9600b data rates. Such radios often have provisions for interfacing external TNCs which are recommended for such applications.

 

At 1200b most KISS mode TNCs will work with Paclink, Telpac, Switch and digi-peater applications with the use of the AGW Packet Engine. Airmail has built-in drivers for a number of TNCs.

 

 

TNCs for 9600 BAUD:

 

KPC-9612, Kantronics

PK-96, AEA

SCS PTC II series with the DSP Packet module

 

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Page last updated SEP 20, 2005

© W3YVQ, 2004-2005, all rights reserved

W3YVQ, Radio-TNC9600bInfoC, AUG 24, 2004

Data provided by the ARRL, Newington, CT, 2004, used with permission