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UHF Wireless Microphone System
By Mike Crofts

The radio microphone marketplace is becoming a busy place these days, but it's always interesting to look at a new system that aims to provide good-quality performance while being very straightforward to set up and operate.

The US1000D system from JTS is based around a PLL synthesized UHF full-diversity receiver and offers options of handheld, headset, lapel and instrument microphones. It can operate on both UK licensed and license-exempt frequencies.

JTS US1000DPhoto: Mike Cameron

In The Hand

The handheld microphone that was supplied with the review setup is designated model MH8990 and has a dynamic capsule, with all the transmitter circuitry built into the mic body. The user guide says that the capsule is 'interchangeable', but there's no other information relating to this in the guide. However, I did discover from the helpful people at UK distributor Proel that there is indeed a condenser option available for a few dollars more.

The main body of the mic is made of metal and has a good, solid feel to it; it's finished in a metallic blue-grey coating that appears tough and is pretty scratch-resistant. I know this because I dropped it on to a hard floor just after unpacking it and luckily there still isn't a mark on it. At the business end is a neat black wire-mesh basket backed by foam, additional protection being provided in the form of a rubber-like cushion ring around the circumference. The basket assembly unscrews complete with capsule. This is an unusual arrangement (it's more common for the capsule to remain fixed in place when you take the basket off), but it seems quite a good idea from a reliability point of view, as the basket assembly holds the capsule firmly in place when it's screwed into position. The capsule looks as if it is clipped in place within the outer basket, and it isn't immediately obvious how to remove it. This would not normally be a problem, unless you wanted to remove a dent from the mesh or clean the foam lining.

At the tail end of the body, a large section of the outer casing unscrews to reveal the battery compartment, which accommodates two standard AA cells. The removable part is made of plastic and incorporates a detachable colour-coded ring, so that individual mics can be identified. This is a useful feature, especially if you're using multiple mics live on stage, as radio mics have a tendency to get swapped about during a show and you obviously can't keep track of them by the colour of the leads! A set of different coloured rings is supplied with the mic.

The whole basket of the handheld mic transmitter unscrews, complete with mic capsule. A condenser capsule/basket assembly can replace the dynamic capsule supplied as standard.The whole basket of the handheld mic transmitter unscrews, complete with mic capsule. A condenser capsule/basket assembly can replace the dynamic capsule supplied as standard.On the bottom plate of the mic body are two recessed slide switches, one for turning the transmitter power on and off and the other for engaging the Mute function. Halfway up the body is a small recessed control and display panel, which allows channel-selection and sensitivity setting by means of three small rubber buttons. The panel displays either the channel group and number or the actual frequency in use, and it also gives an indication of the remaining battery life.

The only problem I had with the handheld mic concerned the two switches — Mute and Power On/Off — on the base; they're very difficult to tell apart, especially in dim light (for example, on stage) and it's easy to turn the mic's power off instead of muting it. This isn't a complete disaster, as in either case the receiver will actually mute the audio path, but turning the power off firstly makes a bit of a noise through the PA and secondly leaves that RF channel unoccupied for a time. It's a small point, but one raised by two singers who tested the mic for me.

The Mute function itself is based on a pilot-tone system and works reliably; the handheld transmitter sends a continuous pilot tone (in the region of 30kHz) when it is powered up and not muted. When Mute is engaged, this tone is no longer transmitted. If the receiver 'loses' the pilot tone, it automatically and quietly mutes the audio output, therefore keeping unwanted system noise to a minimum.

Belting Up

Eight coloured rings are supplied with the handheld mic, to help with identification on stage.Eight coloured rings are supplied with the handheld mic, to help with identification on stage.The PT990B belt-pack transmitter is housed in a plastic case which is, in turn, held within an outer metal sleeve. When the unit is in its normal operating position, all the controls except the on/off switch are hidden by the metal outer sleeve and thus protected from accidental or unwanted operation. The top panel contains the aforementioned power switch, plus a small and very bendy whip aerial, and a four-pin mini-XLR microphone input socket. When the transmitter is slid upwards within the outer metal sleeve, you can gain access to the Up, Down and Set buttons, which select the channel and frequency (as for the handheld transmitter), while sliding the unit downwards reveals the battery compartment (two AA cells). The way this works is a nice touch: here's one piece of kit that will never lose its battery cover.

On the front of the PT990B is a small LCD display that indicates the channel (or actual frequency) of operation and battery status; at the back is a metal belt clip which is strong but easy to use, and looks as if it could be reversed by swapping its mounting to two unused threaded holes, just in case you needed to have the antenna pointing downwards.

Heads Or Lapels

JTS US1000DSliding the cover of the beltpack transmitter one way reveals its control buttons, while sliding it the other way exposes the battery compartment.Sliding the cover of the beltpack transmitter one way reveals its control buttons, while sliding it the other way exposes the battery compartment.The belt-pack transmitter can be used with any of three microphone options, namely headset, instrument or lapel mics.

The headset microphone has recently been upgraded from the one shown in the user guide, and is known as model CM204U. It uses a cardioid condenser capsule mounted on a gooseneck boom, which is in turn hosted by a simple wire headband. Headset mics are among the most 'subjective' items in a live-sound system, as what one user finds comfortable and easy to use will be a source of irritation to another. I asked three singers to try this particular mic, and two found it a bit basic, whereas the third liked the simplicity and negligible weight. The trick is to bend the simple wire headband into various shapes until it fits the head. There's no adjuster strap or anything fancy, but it does the job. All three singers agreed that the mic performed well and were particularly impressed with the stability of the gooseneck part, which has plenty of adjustment and actually stays in place for as long as you want! Sound quality is good, the mic provides plenty of level, and it was always easy to find a good working position for the capsule with a minimum of fuss. According to our engineer Paul, who is a master at adjusting performers' radio mics, a position just below the lip line gave best results with minimum plosive sounds.

The instrument mic is, I believe, of similar construction and specification but wasn't included in the review pack; from the picture in the user guide, it appears to be the sort you can clip on to the bell of a saxophone, and has a short gooseneck stem for adjustment.

The third option is a very neat little lapel mic (the CM201), which is one of the smallest I've seen, certainly in anything like this price range (£34 each, including VAT). Like the headset option, this is a recently upgraded version and is still a condenser, but with an omnidirectional pickup pattern that results in a much more even response when the sound source (the person's mouth) moves around relative to the microphone position. I immediately thought of the numerous theatre shows where I've needed just such a discreet microphone to be located invisibly about a performer's head, and this is definitely an interesting little package. The sound is clear and well-balanced, it's not too susceptible to handling noise, and I feel sure that my own rig will contain half a dozen of these — in the flesh-colour option — later this year for some upcoming theatre gigs.

On The Receiving End

The system receiver is the US1000D, which is a true-diversity UHF device housed in a metal half-rack-size box. The term 'diversity' refers to a receiver with two separate receiver paths, one for each antenna. Whichever antenna is getting the strongest signal is the one the receiver automatically switches to, helping to prevent drop-outs and loss of signal. This receiver also incorporates some clever filtering technology called SAW (Surface Acoustic Wave), which is often used in hi-tech RF applications to prevent specific types of interference from sources such as portable computers.

At only around 5mm in length, the CM201 lapel mic is very unobtrusive in use.At only around 5mm in length, the CM201 lapel mic is very unobtrusive in use.

As in the case of the microphone transmitters, all the setting up is accomplished by the three Up, Down and Set buttons, and there's also a large rotary control for output level. A prominent LCD panel provides various indications, including the selected channel, group and frequency, RF and audio signal levels, diversity path 'A' or 'B' and status indications for Group, Lock and Frequency modes. There's also a battery-status display to show the approximate condition of the transmitter batteries. The display is large and clear, and easy to read in spite of the fact that it contains a fair amount of information. To the left of the front panel, a power on/off switch completes the picture.

The straightforward rear panel hosts just five connectors — two antenna-input sockets of the good old 'turn to lock' BNC variety, balanced XLR and unbalanced jack audio outputs, and a DC power-input point which is where the 12V adaptor (fortunately, an in-line type, rather than a plug-top thing) is connected.

The antennae are chunky, covered in some kind of plastic/rubber material and just flexible enough to avoid damage if knocked. The BNC connectors mate positively and easily and there's plenty of adjustment available for positioning the two antennae as required.

The headset mic has a very simple wire headband but works well in practice.The headset mic has a very simple wire headband but works well in practice.

Setting Up

The system really is very easy to set up and get running, and one of the reasons for this is the channel grouping facility: you can choose to display and set either the actual channel frequencies, of which there are many (total system capability is up to 961) or to display the available channels in preset groups, which is a much easier method. The system offers four groups — A B C and D — each of which contains 16 preset channels that will operate properly together in a system. It's therefore really simple to set up using these groupings; in fact, most of the time you'd probably leave them set to the same group. Having selected the (same) channel on both the transmitter and the receiver, you can adjust the microphone sensitivity to one of four settings, between 0dB and -24dB.

A nice feature of the JTS system is the 'lock-on' function, which provides protection against inadvertent changing of channels on transmitter or receiver. When the channel has been selected and lock-on enabled, you have to go through the various steps of removing lock-on before the channel can be changed. If lock-on is activated, pressing any button will result in a 'loc on' messsage appearing on the display.

  The US1000D receiver. The US1000D receiver.

In Practice

In a live test, the performance of this system lived up to the specifications in all respects. The microphone options all work well and and the handheld mic is equally at home with male and female vocals, having a punchy and lively quality very much in keeping with what you'd expect from a decent dynamic vocal mic. If you prefer using stage condensers, you can order a condenser capsule with the system for an extra £47 including VAT. Being metal-bodied, the mic is heavier than some but has a good, solid feel and does appear to be very well put together. Audio performance is fine, especially with the recently upgraded condenser microphone options, and the RF side is stable. There's not a lot wrong with this JTS system, in my humble opinion: it does exactly what it's supposed to, and it does it very well. 



  • Good audio and RF performance.
  • Lots of channels with useful preset group function.
  • Easy to set up and operate.
  • Solid build.
  • Remote battery indication is very useful for live events.


  • Headset mic frame is very basic.
  • Mute and Power switches on base of handheld mic need clearer identification.


The JTS US1000D system provides a good level of audio and RF performance, is reasonably priced and well made, and has one or two useful extra features that make it very easy to use.


US1000D/A (system with handheld dynamic mic), US1000D/B (with lapel mic) and US1000D/G (with belt-pack and instrument lead) £351.32 each; US1000D/C (with headset mic) £381.87. Prices include VAT. Various components also available separately.

Proel International +44 (0)20 8761 9911.

Published June 2006