275:
PAL from non-PAL lines, and produces the IDENT signal at 7.8 kHz half the line scan of 15,625 kHz. As in the NTSC system, U and V are used to modulate the color subcarrier using two balanced modulators operating in phase quadrature: one modulator is driven by the subcarrier at sine phase; the other modulator is driven by the subcarrier at cosine phase. The outputs of the modulators are added together to form the modulated chrominance signal: C=Usin ωt±Vω=2πFSC FSC=4.43361875 MHz(±5 Hz) for (B, D, G, H, I, N) PALFSC=3.58205625 MHz (±5 Hz) for (NC)PALFSC=3.57561143 MHz(±10 Hz) for (M)PAL
279:
errors produce complementary errors, allowing line-to-line averaging at the receiver to cancel the errors and generate the correct hue with slightly reduced saturation. This technique requires the PAL receiver to be able to determine the correct V phase. This is done using a technique known as AB sync, PAL sync, PAL switch, or swinging burst, consisting of alternating the phase of the color burst ten cycles long, by ±45° at the line rate hence colour phase errors are reduced or not evident watching TV pictures.
296:
63:
22:
173:
274:
This colorburst is sometimes called a "swinging burst", since it swings plus or minus 45 degrees line by line (hence the expression "phase alternating line"). This swing is used to set the centre frequency of the colour reference oscillator in the decoder. The swing of the burst phase distinguishes
278:
In PAL, the phase of V is reversed every other line. V was chosen for the reversal process since it has a lower gain factor than U and therefore is less susceptible to a one-half FH switching rate imbalance. The result of alternating the V phase at the line rate is that any color subcarrier phase
191:
333:
263:
format. The frequency of this burst is 4.43361875 MHz; it is precise to 0.5 Hz, and is used as the reference frequency to synchronise the
227:
209:
154:
49:
352:
326:
88:
135:
260:
107:
84:
35:
357:
114:
319:
252:
73:
121:
92:
77:
103:
244:
264:
41:
128:
303:
268:
346:
62:
295:
248:
256:
166:
56:
15:
307:
187:
182:
may be too technical for most readers to understand
327:
8:
91:. Unsourced material may be challenged and
50:Learn how and when to remove these messages
334:
320:
228:Learn how and when to remove this message
210:Learn how and when to remove this message
194:, without removing the technical details.
155:Learn how and when to remove this message
302:This electronics-related article is a
192:make it understandable to non-experts
7:
292:
290:
251:in the "porch" of the synchronising
89:adding citations to reliable sources
14:
31:This article has multiple issues.
294:
171:
61:
20:
267:of the colour decoder in a PAL
39:or discuss these issues on the
1:
306:. You can help Knowledge by
261:broadcast television systems
374:
289:
259:(Phase Alternation Line)
353:Television technology
85:improve this article
358:Electronics stubs
315:
314:
265:local oscillators
243:is the first ten
238:
237:
230:
220:
219:
212:
165:
164:
157:
139:
54:
365:
336:
329:
322:
298:
291:
233:
226:
215:
208:
204:
201:
195:
175:
174:
167:
160:
153:
149:
146:
140:
138:
97:
65:
57:
46:
24:
23:
16:
373:
372:
368:
367:
366:
364:
363:
362:
343:
342:
341:
340:
287:
285:
234:
223:
222:
221:
216:
205:
199:
196:
188:help improve it
185:
176:
172:
161:
150:
144:
141:
98:
96:
82:
66:
25:
21:
12:
11:
5:
371:
369:
361:
360:
355:
345:
344:
339:
338:
331:
324:
316:
313:
312:
299:
284:
281:
269:television set
236:
235:
218:
217:
179:
177:
170:
163:
162:
69:
67:
60:
55:
29:
28:
26:
19:
13:
10:
9:
6:
4:
3:
2:
370:
359:
356:
354:
351:
350:
348:
337:
332:
330:
325:
323:
318:
317:
311:
309:
305:
300:
297:
293:
288:
282:
280:
276:
272:
270:
266:
262:
258:
254:
250:
246:
242:
232:
229:
214:
211:
203:
193:
189:
183:
180:This article
178:
169:
168:
159:
156:
148:
145:December 2009
137:
134:
130:
127:
123:
120:
116:
113:
109:
106: –
105:
104:"Burst phase"
101:
100:Find sources:
94:
90:
86:
80:
79:
75:
70:This article
68:
64:
59:
58:
53:
51:
44:
43:
38:
37:
32:
27:
18:
17:
308:expanding it
301:
286:
277:
273:
240:
239:
224:
206:
200:January 2012
197:
181:
151:
142:
132:
125:
118:
111:
99:
83:Please help
71:
47:
40:
34:
33:Please help
30:
241:Burst phase
347:Categories
283:References
249:colorburst
115:newspapers
36:improve it
72:does not
42:talk page
255:in the
186:Please
129:scholar
93:removed
78:sources
245:cycles
131:
124:
117:
110:
102:
253:pulse
136:JSTOR
122:books
304:stub
108:news
76:any
74:cite
257:PAL
247:of
190:to
87:by
349::
271:.
45:.
335:e
328:t
321:v
310:.
231:)
225:(
213:)
207:(
202:)
198:(
184:.
158:)
152:(
147:)
143:(
133:·
126:·
119:·
112:·
95:.
81:.
52:)
48:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
