Reprinted from “Fundamentals of Sailing, Cruising, & Racing” by Steve Colgate; published by W.W. Norton & Co.

Another drill one hopes never to have to use is sailing without a rudder. Though you may sail 20 years without loosing your rudder at sea, it could happen your first time out. You can control the direction of the boat by changing the efficiency of the sails fore and aft. By luffing the jib and trimming the main, we create weather helm and the boat turns into the wind. By luffing the main and flattening the jib, the wind pushes the bow to leeward – in other words, lee helm. To practice this, trim your jib reasonably flat and ease your mainsail until the boat is balanced and sails straight ahead when the helm is released. Then change your course by trimming the main to head up and pushing the boom out to fall off. When the bow starts swinging in one direction, you must immediately begin the opposite procedures to counteract the swing.

In order to tack, free the jib sheets and trim in the mainsail hard and fast. As soon as the boat is past head-to-wind, trim the jib and ease the main to force the bow down. If necessary, back the jib.

Jibing is much more difficult to do without the rudder because the mainsail causes the boat to turn toward the wind when running. To try it, ease the main completely, making sure the boom vang is also loose, and back the jib to windward. As you fall off to a run, move all the crew to the windward side of the boat and hike out. By heeling the boat to weather, lee helm should be created. Just as a bow wave on the lee side pushes a heeling boat to weather, a bow wave on the windward side (caused by healing the boat to windward) pushes the bow to leeward. In this case, we are using crew weight to help a rudderless jibe, but at other times crew members hike out to weather, not only when closehauled, but on reaches and runs to reduce weather helm.

If the breeze is very light, we can make minor adjustments to the helm by moving the crew weight forward and aft. With the boat balanced as described above, move the crew well forward toward the bow. The boat will head into the wind as the curve of the bow bites more deeply into the water. By moving the crew to the stern, the bow will fall off to leeward.

Happy Sailing from Steve Colgate, founder of Offshore Sailing School!

在 整 個 經 濟 體 系 內 的 貨 幣 總 量 。 香 港 貨 幣 供 應 量 的 指 標 有 3 個 ：

貨 幣 供 應M1 是 指 市 民 持 有 的 法 定 貨 幣 （ 包 括 紙 幣 及 硬 幣 ） 與 銀 行 客 戶 的 活 期 存 款 。

貨 幣 供 應M2 是 指 貨 幣 供 應M1 所 包 括 的 項 目 ， 再 加 上 銀 行 客 戶 的 儲 蓄 及 定 期 存 款 ， 以 及 由 銀 行 發 行 並 由 非 銀 行 持 有 的 可 轉 讓 存 款 證 。

貨 幣 供 應M3 是 指 貨 幣 供 應M2 所 包 括 的 項 目 ， 再 加 上 有 限 制 牌 照 銀 行 及 接 受 存 款 公 司 的 客 戶 存 款 ， 以 及 由 這 兩 類 機 構 發 行 並 由 非 銀 行 持 有 的 可 轉 讓 存 款 證 。

在 這3 個 貨 幣 供 應 指 標 中 ， 港 元 貨 幣 供 應 M1 的 數 字 有 明 顯 的 季 節 性 變 化 ， 廣 義 貨 幣 （ 即 港 元 貨 幣 供 應 M2 與 M3 ） 則 沒 有 。 金 管 局 定 期 編 製 及 公 布 就 季 節 因 素 作 出 調 整 的 港 元 貨 幣 供 應 M1 及 其 組 成 部 分 （ 即 公 眾 持 有 的 現 金 與 活 期 存 款 ） 。

貨 幣 供 應M1 是 指 市 民 持 有 的 法 定 貨 幣 （ 包 括 紙 幣 及 硬 幣 ） 與 銀 行 客 戶 的 活 期 存 款 。

貨 幣 供 應M2 是 指 貨 幣 供 應M1 所 包 括 的 項 目 ， 再 加 上 銀 行 客 戶 的 儲 蓄 及 定 期 存 款 ， 以 及 由 銀 行 發 行 並 由 非 銀 行 持 有 的 可 轉 讓 存 款 證 。

貨 幣 供 應M3 是 指 貨 幣 供 應M2 所 包 括 的 項 目 ， 再 加 上 有 限 制 牌 照 銀 行 及 接 受 存 款 公 司 的 客 戶 存 款 ， 以 及 由 這 兩 類 機 構 發 行 並 由 非 銀 行 持 有 的 可 轉 讓 存 款 證 。

在 這3 個 貨 幣 供 應 指 標 中 ， 港 元 貨 幣 供 應 M1 的 數 字 有 明 顯 的 季 節 性 變 化 ， 廣 義 貨 幣 （ 即 港 元 貨 幣 供 應 M2 與 M3 ） 則 沒 有 。 金 管 局 定 期 編 製 及 公 布 就 季 節 因 素 作 出 調 整 的 港 元 貨 幣 供 應 M1 及 其 組 成 部 分 （ 即 公 眾 持 有 的 現 金 與 活 期 存 款 ） 。

本港首隻人民幣新股，匯賢產業信託(87001.HK)首日上市，跌穿招股價，低位見4.83元，當時跌近百分之八。現回穩到5元水平，仍比招股價低近百 分之三。 對於首隻人幣新股首日即潛水，港交所(00388.HK)行政總裁李小加表示，人民幣新股始終是新嘗試，今年內希望還有其他的人民幣新股出現。 他指，人民幣產品的發展，必須配合市場需要，若僅僅將本地已有的投資產品變為人民幣計價，作用不大，最重要是在人幣國際化進程中，讓內地投資者走到海外 時，以本港作為平台，才是最重要。而交易所作為市場營運者，最重要是做好基建，在機制上便利人民幣產品的發展，例如透過人證港幣交易通，紓緩人民幣資金量 不足的問題。 在被問到港股直通車問題時，李小加指，他個人認為，內地容許資金投資境外市場，這個「放水」是將來大趨勢，但必須有管制，否則若放洪水，會沖毁境外設施。 港交所主席夏佳理表示，股票價格是由市場決定，但不代表投資者不認同人民幣股票。

Jan 27,2010 00:00 by infomar
Digital Selective Calling is the fundamental reason why the GMDSS system is different from what has been available until now. Prior to DSC, most radio calls were initiated by making a voice call to the desired station, and relying on somebody at that station hearing the call and then responding to it. All too often the sheer volume of calls made this an impossible task. On a summer afternoon in popular sailing areas it was not unusual for there to be over 400 calls per hour on VHF channel 16. At best, this made it very tedious, and often impossible, to hear calls meant for you, or more importantly, for anybody to hear a distress call. Clearly, something had to be done.

Initially a partial answer was found by shifting some of the calling traffic off channel 16. In some areas Coast Stations stopped monitoring channel 16 and listened for calls only on their working channels. Similarly, calls to marinas were stopped on 16 and moved to other designated channels. That relieved some of the pressure, but now there was no single channel that everybody was listening to, so vessels missed calls meant for them and distress calls sometimes went unheeded.

On board commercial ships, the problem was even worse. They were not only expected to monitor channel 16, but also 13 for bridge-to-bridge calls, 2182 MHz on MF, and if on the high seas, one or more HF distress frequencies. What a headache – literally! The salvation lay in DSC. The DSC control unit monitors all the required frequencies, and lets the operator know when there is a call for his station, or when there is a distress or other urgent call. Best of all, it does all this in total silence. No longer are we subjected to the continuous cacophony on channel 16 nor the static crashes and bangs on 2182 MHz. Instead, we wait for the phone to ring, as it were.

How DSC Works

How is this miracle achieved? The DSC control unit is somewhat like a pager which alerts the receiving station that there is traffic waiting for them. The name, Digital Selective Calling, goes a long way to explaining how it works.

DSC uses a Digital signal to send a message, via the sending station’s radio, to alert the receiver that there is traffic for them, and to tell them where and how to receive the traffic. This DSC message is termed a DSC Call, or sometimes a DSC Alert. The digital message includes several pieces of information which will be displayed on the receiving station’s DSC control unit:

1. The Maritime Mobile Service Identity of the sending station. The MMSI is a nine digit number, and it is the DSC equivalent to the call sign, or the ‘phone number’ of a station. It is issued as part of the GMDSS station licence.

2. The MMSI of the station being called. This can be an individual vessel or Coast Station, a specific group of vessels, or in the case of distress, urgency or safety traffic, to all stations.

3. The priority of the call – distress, urgency, safety or routine. DSC can be used for setting up any type of call, from a Mayday to making a phone call home.

4. For distress calls, the DSC alert can include the nature of the distress, e.g. fire, sinking, explosion, pirate attack etc.

5. For distress calls the position of the vessel is normally included. If the control unit is interfaced to a Global Positioning System receiver, then the position will be added automatically. If there is no GPS receiver connected to it, then the position, and the time that the position was valid, must be keyed in.

6. The requested working frequency and mode of transmission for the traffic. The DSC is only used to set up the call; the actual communication is conducted on another radio channel – distress or working channel as the case may be – and it can be conducted in either voice or telex mode, depending on circumstances.

DSC calls are Selective, because as we have seen above, they can be directed to a selected station or stations. Previously virtually all calls were received by all stations who were in range of the transmission. However, the DSC control unit looks at each call that it receives and determines if the call is addressed to it specifically, to it as part of a group, to all stations, or to vessels in the area where the receiving station is located. When such a call is received then the operator is alerted, usually by a buzzer and an indication on the screen. The information as to where and how the traffic will be sent is displayed on the screen. All other calls are simply ignored.

The last part of the name sums up what DSC is about. It is used for calling another station to advise them that there is traffic for them, and to what channel or frequency they should tune their radio to receive this traffic. When a DSC call is transmitted by VHF, it is sent in F1B modulation, at a speed of 1,200 baud. At this speed, all the data in a DSC Alert can be transmitted in about half a second. On MF/HF things happen just a little slower. The modulation is J2B and the speed of transmission is 100 baud. This results in a DSC Alert on MF or HF taking between 6 and 7 seconds to be transmitted. The DSC control unit transmits the DSC calls through the ship’s VHF and/or MF/HF radio. Although installations and equipment obviously vary, the control unit is normally also connected to a dedicated receiver which monitors the DSC frequencies for incoming DSC calls, regardless of to which frequencies the ship’s radios are tuned.