Ten-Tec_Jupiter_538_review_2004.pdf

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1、REVIEW 33January 2004 RadCom www.rsgb.org Reviewed by Peter Hart, G3SJX, The Willows, Paice Lane, Medstead, Alton, Hants GU34 5PR. I n 1999 Ten-Tec introduced the Pegasus transceiver, a fully fea- tured HF radio for use with a Windows PC. There was no front panel as such, just a box fitted with sock

2、ets and a power switch and with all control via the PC monitor, keyboard and mouse. In 2000 Ten- Tec took the Pegasus design and added a conventional front panel, controls and display to make a standalone radio. Thus was born the Jupiter. The same feature set is retained and also the PC interface so

3、 the radio can also emulate the Pegasus in PC control mode with software freely downloadable from the Ten-Tec website. The transceiv- ers firmware is held in flash memo- ry and can be updated at any time by downloads from the Ten-Tec website. New features can be added: a recent update provides for 5

4、MHz transmit coverage. Although the Jupiter has been available in the USA for some time, it has only recently received CE approval for sales within Europe. It is available in two versions, model 538 without auto ATU and model 538AT with internal auto ATU fitted. The ATU can be fitted at a later date

5、 if need- ed. The non-ATU version was the model supplied for review. BASIC FUNCTIONS The Jupiter is a table-top sized 12V operated radio measuring 308W x 144H x 350Dmm and weighs about 5.5kg. The receiver tuning range is specifi ed from 100kHz to 30MHz but it continues to tune all the way down to DC

6、 although the sensitivity at low frequencies is very much reduced. The transmit segments are confi ned to the amateur bands with a bit to spare and the transmit power is nominally 100W maximum. Modes covered are USB, LSB, CW, AM and FM. Digital modes make use of the SSB modes with AFSK input. A menu

7、 item toggles the transmit audio source between the microphone and the accessory jack on the rear panel. The receiver bandwidth can be tai- lored to suit the different tone stan- dards by suitable adjustment of the bandwidth and PBT (passband tun- ing) controls but no frequency dis- play offset is p

8、rovided. The Jupiter front panel is clearly laid out with spacious buttons and good-sized controls. As every control except the power on/off switch may be computer operated, the rotary controls are all digital encoders. Dedicated rotaries are used for the main tuning, RIT, bandwidth and PBT and a mu

9、ltifunction rotary con- trol is switchable to other functions such as RF and AF gain, power out- put, microphone gain and squelch. Surprisingly, the AF gain control is not a dedicated rotary so I left the The Ten-Tec Jupiter HF transceiver A DSP transceiver that may easily be PC controlled, the Jupi

10、ter is the latest from the US Ten-Tec stable. multifunction control normally set to this position. A large green back- lit LCD panel is used for the display giving a clear indication of the fre- quencies of the twin VFOs and the state of the switchable functions. A bargraph meter for the S-meter fun

11、ction and transmit power or VSWR also gives the numerical value and a separate slide rule bar- graph shows the levels associated with the multifunction rotary also with a numerical percentage of the maximum. The rear panel carries the usual interface connectors. Phono sockets are used for T/R functi

12、ons including handshaking support for QSK lin- ears, two auxiliary 12V outlets and a spare for custom use. DIN connec- tors are provided for interfacing accessories such as data terminals, sound card connections and an optional keypad. A 9-pin D connector interfaces directly to the PC serial COM por

13、t without the need for level conversion. I was surprised at how much space there is inside the cabi- net but note that a Torx driver is needed to remove the screws. The radio could have been made signifi - cantly smaller but for a radio intend- ed for home station use that is not necessarily an adva

14、ntage. A 75mm speaker fi ts in the upper case top. There is a heatsink on the rear panel but no fan is fi tted, the radio shut- ting down if the heatsink tempera- ture exceeds 85C. An optional fan is available but is claimed not to be necessary unless transmitting key down for extended periods such

15、as in RTTY contests. The receiver is a triple superhet with IFs of 45MHz, 455kHz and 12kHz. Most of the signal processing including receiver IF filtering func- tions is implemented by DSP at the 12kHz IF. The receiver front end uses a push-pull FET first mixer and three parallel FETs in the RF ampli

16、- fier. The RF amplifier is in-circuit all the time but there is a switchable 20dB attenuator for very strong sig- nal situations. Conversion to the second and third IFs uses diode bal- anced mixers and gain is carefully controlled up-front of the DSP with AGC applied to the RF amplifier and first I

17、F stages. AGC detection is done partly by the DSP but also at the second IF so there can be some AGC control from big signals outside of the main filter passband but inside the roofing filter bandwidth. The local oscillator drive for the first mixer is derived from a single loop PLL tuning in 2.5kHz

18、 steps. The smaller tuning step sizes are accom- modated within the DSP. Hence the signals within the IFs move by up to 2.5kHz. A built-in TCXO reference ensures good frequency accuracy and stability. As standard, the Jupiter trans- ceiver is provided with various plugs and leads including a full ac

19、cessory jack lead and a microphone plug, but the microphone is an extra. The radio accommodates most micro- phone types including electret and Ten-Tec supply hand and desk mod- els. The radio is shipped with a com- prehensive operators manual cover- ing the installation and operation and a full set

20、of circuit descriptions, schematics and part lists. However, I did come across numerous errors in the manual. FEATURES Most of the features of the radio are clearly implemented and easy to select. Some of the lesser-used func- tions are accessed via the menu sys- tem but this is also easy to access.

21、 A band button scrolls through the bands and a mode button through the modes. The 50mm diameter rotary tuning knob tunes in a variety of step sizes from 1Hz to 100kHz but at only 120 steps per knob revolu- tion. The usual twin A/B VFOs are provided with facilities for split oper- ation and the frequ

22、encies of both are continuously displayed. 128 memo- ries are available for storing frequen- cies and mode and RIT and XIT are both provided giving offset tuning up to 8kHz. All selectivity related features are implemented in DSP. 34 different receiver bandwidth settings between 300Hz and 8kHz may b

23、e selected by a rotary control on all modes and a separate PBT rotary control shifts the bandwidth by up to 8kHz in 10Hz steps. This is useful for com- bating QRM and optimising the passband on data modes. The effec- tive selectivity curve on USB, with the bandwidth set at 2.4kHz, is shown in Fig 1.

24、 DSP noise reduction may be selected which is effective at removing broadband noise by up to 15dB and an automatic notch oper- ates at audio which is reasonably effective at removing continuous heterodynes. Other receive func- tions include an impulse noise blanker selected via the menu sys- Fig 1:

25、Jupiter effective selectivity curve on USB (bandwidth 2.4kHz). The Jupiters rear panel. REVIEW 34January 2004 RadCom www.rsgb.org -30-25-20-15-10-50+5+10+15+20+25+30 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 Frequency offset (KHz) Response (dB) single tone dynamic range IF fi lter respons

26、e Oscillator sideband noise RADCOM 058 Fig 1 tem, three selectable AGC speeds, an all-mode squelch and high boost tone control. On transmit, the power output is adjustable from a few watts to 100W, a selectable speech proces- sor is provided and the transmit audio response may be tailored to suit in

27、dividual preferences. DSP fil- tering provides 18 bandwidth set- tings from 900Hz to 3900Hz and the low frequency roll-off is adjustable. This last menu item was added during a firmware update and post-dates the current manual. An audio monitor and VOX facilities are also provided but to use the Ten

28、-Tec hand microphone on VOX the short across the mic insert on receive should be removed from the PTT switch. A tune button trans- mits a carrier on all modes at either the selected power level or at the 10W level. On CW, full QSK with adjustable delay and support for both QSK and non-QSK linears is

29、 provided. CW sidetone and pitch may be set over a wide range and a spot button pro- vides an accurate netting tone. A built-in keyer for external paddles may be selected operating over the wide range of 1 to 63WPM. The dot/dash weighting is fi xed but the dot/space weighting is adjustable. There ar

30、e no memories or contest modes. The Jupiter includes a sweep and spectrum display facility with eight selectable sweep widths from 240Hz to 2.4MHz. These are dis- played at a high resolution of 240 frequency steps per scan and the receiver is briefly muted whilst the sweep is in progress. An auto mo

31、de can select a fresh sweep when changing bands or frequencies out- side the scan range. PC CONTROL Software downloads to update the firmware and for Pegasus emulation control are available free of charge from the Ten-Tec technical support website (see Websearch below). Both downloads are about 750K

32、B each and are executable files which install easily and link to the radio via a serial COM port. During the period I had the radio, I upgraded the firmware from v1.24 to v1.26 which took about 40 seconds. The Pegasus control software seemed fairly undemanding and I had it running satisfactorily in

33、Windows 3.1, 98 and XP with machine speeds from 25MHz to 2GHz. When the Pegasus control soft- ware is started, the radio switches automatically to PC control mode showing a virtual front panel on the PC monitor. Local front panel set- tings are stored and the remote Pegasus settings enabled. Similar

34、ly exiting Pegasus mode stores the CLOSE-IN DYNAMIC RANGE MEASUREMENTS ON 7MHz BAND RECIPROCAL FREQUENCY3rd ORDERTWO TONEBLOCKINGMIXING FOR SPACINGINTERCEPTDYNAMIC RANGE3dB NOISE 3kHz-26dBm67dB-34dBm68dB 5kHz-14dBm75dB-33dBm71dB 7kHz-10dBm78dB-23dBm74dB 10kHz-5dBm81dB-13dBm78dB 15kHz+1.5dBm86dB-8dBm

35、82dB 20kHz+4dBm87dB-6dBm84dB 30kHz+5dBm88dB-6dBm88dB 40kHz+6dBm89dB-6dBm90dB 50kHz+6dBm89dB-6dBm92dB 100kHz+6dBm89dB-6dBm99dB 200kHz+6dBm89dB-6dBm106dB TRANSMITTER MEASUREMENTS CWINTERMODULATION POWERPRODUCTS FREQUENCYOUTPUTHARMONICS3rd order5th order 1.8MHz100W-56dB-32 (-26)dB-41 (-35)dB 3.5MHz100W

36、-57dB-28 (-22)dB-39 (-33)dB 5.4MHz91W-62dB-28 (-22)dB-41 (-35)dB 7MHz98W-49dB-30 (-24)dB-38 (-32)dB 10MHz99W70dB 1kHz Transmitter AF distortion: 1% Microphone input sensitivity: 7 - 40mV FM deviation: see text SSB T/R switch speed: mute-TX 20ms,TX-mute 12ms, mute-RX 40ms, RX-mute 4ms NOTE:All signal

37、 input voltages given as PD across antenna terminal. Unless stated otherwise, all measurements were made on USB with a 13.8V supply and 2.4kHz bandwidth setting. RECEIVER MEASUREMENTS SENSITIVITY FREQUENCYSSB 10dBs+n:nINPUT FOR S9 1.8MHz0.56V (-112dBm)63V 3.5MHz0.40V (-115dBm)40V 5.4MHz0.32V (-117dB

38、m)35V 7MHz0.32V (-117dBm)35V 10MHz0.35V (-116dBm)40V 14MHz0.35V (-116dBm)45V 18MHz0.40V (-115dBm)50V 21MHz0.49V (-115dBm)50V 24MHz0.45V (-114dBm)56V 28MHz0.50V (-113dBm)70V AM sensitivity (28MHz): 2.2V for 10dBs+n:n at 30% mod depth FM sensitivity (28MHz): 0.45V for 12dB SINAD 3kHz pk deviation AGC

39、threshold: 18V 100dB above AGC threshold for 0.5dB audio output increase AGC attack time: 2ms (see text) AGC decay time: 100ms (fast), 1s (medium), 8s (slow) Max audio at 5% distortion: 1.0W into 4 (see text) Inband intermodulation products: -20dB to -40dB S-READINGINPUT LEVEL (7MHz)SSB S30.5V S52.2

40、V S79.0V S935V S9+20350uV S9+402.5mV S9+60100mV FILTERIF BANDWIDTH -6dB-60dB 6kHz5675Hzsee text 3.9kHz3710Hzsee text 2.4kHz2418Hzsee text 1.8kHz1837Hzsee text 900Hz988Hzsee text 525Hz660Hzsee text 300Hz472Hzsee text INTERMODULATION (50kHz Tone Spacing) 3rd order2 tone Frequencyinterceptdynamic range

41、 1.8MHz+6.5dBm86dB 3.5MHz+6.5dBm88dB 7MHz+6dBm89dB 14MHz+9dBm90dB 21MHz+10dBm90dB 28MHz-3dBm80dB TEN-TEC JUPITER MEASURED PERFORMANCE 35January 2004 RadCom www.rsgb.org remote settings and returns the local settings, settings cannot be shared. Emulation of the rotary tun- ing knob is rather slow and

42、 cumber- some but an optional remote keypad and tuning knob directly equivalent to that on the front panel is avail- able. Sliders are used instead of rotary controls and a fast tuning slider speeds rapid frequency changes. Many facilities are better implemented, eg separate buttons for modes and al

43、so for bands and there are a number of additional features not available on the Jupiter alone. Memory stores are much more comprehensive with various text fields and sweep functions are more informative. Overall a worth- while addition and a different oper- ating experience. MEASUREMENTS Measurement

44、s shown in the table were made with the review radio pow- ered from a 13.8V supply and the receiver bandwidth set to 2400Hz. The supplied power cable looks rather thin but only dropped 0.2V under full transmit output. The receive sensitivity is lower than most radios but still entirely adequate for

45、practical antennas. Below 500kHz the sensitivity drops away sharply, measuring 140V at 136kHz for 10dB s+n:n. The overall gain is also quite low with the AGC threshold set at about S8 (18V). This yields a quiet background noise level but weak signals give less audio than strong ones unlike many radi

46、os. S-meter range and linearity are excellent and spurii and images fair- ly low. A number of low level birdies can be heard across the tuning range but none are of consequence within the amateur bands. The third order intercept is reasonable but the lower sensitivity yields a below average two tone

47、 dynamic range. Reciprocal mix- ing is also fairly poor. The DSP IF fi l- ters have excellent fl atness and steep sides but meaningful measurements at -60dB were compromised by the effects of oscillator noise (reciprocal mixing) and AGC action. A wide range of AGC decay times are provid- ed but the

48、attack time suffered 10ms or more overshoot. The audio output could be driven to at least 2W but at this level it overheated and collapsed after a few seconds. Note that the speaker drive is balanced and neither side of the external speaker output should be grounded. When tuning close to carriers st

49、rong clicks could be heard every 2.5kHz. This is a con- sequence of the synthesiser architec- ture adopted in this radio and was also observed during on air testing. Transmit SSB intermodulation products were generally quite reason- able and not signifi cantly degraded by the speech processor. CW keying was clean with low distortion and reasonable rise and fall times although the fi rst attack edge was noticeably sharper. Full QSK and delayed QSK gave identical results. On FM there did not appear to be a deviation limiter but deviation was about 1.5kHz with the microphone gain set as